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What specific genetic or physiological adaptations enable certain bird species to adjust their migration routes in response to climate change or habitat loss?
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[1] Query: bird migration genetic adaptations climate change
Title: [PDF] Genetics and Evolution of Bird Migration
URL: https://www.mbzraptorfund.org/wp-content/uploads/2025/05/Gu-et-al.-2024.-Genetics-evolution-of-bird-migration.-Ann.-Rev.-Anim.-Biosci.pdf
Snippet:  and deepening our understanding of bird migration (e.g., 43, 47).
However, we are currently in the Anthropocene era, a period marked by rapid climate change, such as the unprecedented rising of global temperature, due mainly to human activities (135). As temperatures continue to rise,many bird species have been found to change their migratory strate-gies, with some birds advancing their migration time (136, 137), potentially resulting in reduced breeding success rates (138). Additionally, rising temperatures can alter the migration distance of birds, with long-distance migratory birds being at risk of losing breeding and wintering habitats, as well as facing longer migration distances, due to intensified global warming (139).
Moreover, the changes in climate could also cause birds to evolve new migration routes (Figure 2c). One example is Richard’s pipit (Anthus richardi), a migratory songbird that breeds in the Siberian grasslands and winters in Southeast Asia. Dufour et al. (140) found that the species has become a regular autumn and winter visitor to western Europe only recently, likely because of an increase of wintering niche suitability due to climate change.
Despite some migratory bird species being able to adapt or respond quickly to climate change, it may be insufficient to mitigate the adverse impacts of climate change on their migratory patterns.
For instance, Schmaljohann & Both (141) conducted a review of 49 tracking studies and quantified the potential range of adjusting spring arrival dates through modifying migration speeds. They found that among-individual variation in migration speed was determined mainly by the relatively short stopover duration. By assuming that this population response reflects individual phenotypic plasticity, they calculated the potential for phenotypic plasticity to speed up migration by reducing stopover duration. However, the flexibility in the major determinant of migration duration seems insufficient to adjust to ongoing climate change and is unlikely to explain some of the observed arrival advancements in long-distance migrants (141). Similarly, a meta-analysis of 71 bird studies showed that species with adaptive phenotypic responses may be evolving too slowly to keep pace with global climate change (142).
www.annualreviews.org • Genetics and Evolution of Bird Migration 35 Annu. Rev. Anim. Biosci. 2024.12:21-43. Downloaded from www.annualreviews.org Access provided by 2a00:f29:2c8:8d99:4961:b044:a192:dd0d on 02/26/24. See copyright for approved use. 5. CONCLUDING REMARKS AND FUTURE PROSPECTS The study of the genetics and evolution of bird migration is a constantly evolving field that has witnessed significant advances in recent years. Looking ahead, there are several promising areas for future research in this enigmatic field.
5.1. Molecular Mechanisms of Migration Although past studies have shown that genetics plays an important role in migratory strategies, we still have much to learn about the specific genes, gene interactions, and molecular pathways involved. T o gain a deeper understanding of molecular mechanisms of migration, future research should use omics technologies to study the genetic basis across a wide range of bird species. By comparing genomes of different bird species or populations with varied migratory strategies, re-searchers can identify target genes and genetic variations associated with migration and investigate their evolutionary origins. This approach has already yielded valuable insights into the genetic basis of migration and is highly likely to continue to contribute to our understanding of bird migration in the future.
5.2. Elaborate Functional Experiments Previous studies using various methods such as candidate genes, genomics, transcriptomics, and epigenetics have identified numerous genetic variations relevant to migration behavior; most, however, still lack evidence of functional significance. In addition, to our knowledge, there is still no implementation of gene-editing technology in the study of migratory birds. Therefore, more elaborate functional experiments are needed to fully understand the direct effects of these identified genetic loci on bird migration. Meanwhile, it is also important to evaluate and control the potential risks associated with genetically modified organisms once they are released to the wild.
5.3. Evolutionary Origin of Bird Migration Studying the evolutionary origin of bird migration is an area of active research. The use of phylogenetic and phylogeographic approaches has spurred significant progress in this field, but many important questions remain unexplored (e.g., Where are the evolutionary origins of bird migration?). With more and more bird genomes being sequenced, systematic tests on various hy-potheses using phylogenomic-based methods, along with reconstructed long-term paleoclimate or geochemistry data, could facilitate our understanding of the evolution of bird migration.
5.4. Migratory Strategies in Response to Climate Change The impacts of climate change on migratory birds are a significant concern, as changing climate conditions can disrupt migratory patterns and threaten the survival of these

 species. T o better understand how migratory birds respond to climate change, future research could investigate the evolved strategies of these birds in response to such changes and identify adaptive genes that may hinder or facilitate their future survival. This knowledge will be key to developing target strategies for mitigating the impacts of climate change on migratory birds.
In summary, although the prospect is promising, research on the genetics and evolution of bird migration is still as full of challenges as ever. One such challenge is how to effectively process and analyze large amounts of data, especially when more and more whole-genome and real-time tracking data are produced. The solution is far beyond classical fields such as animal behav-ior or genetics, but luckily, interdisciplinary collaborations have already begun to form between researchers from different fields, such as mathematics, physics, and biology.
36 Gu • Dixon • Zhan Annu. Rev. Anim. Biosci. 2024.12:21-43. Downloaded from www.annualreviews.org Access provided by 2a00:f29:2c8:8d99:4961:b044:a192:dd0d on 02/26/24. See copyright for approved use. DISCLOSURE STATEMENT The authors are not aware of any affiliations, memberships, funding, or financial holdings that might be perceived as affecting the objectivity of this review.
ACKNOWLEDGMENTS This study was supported by National Natural Science Foundation of China grants 32125005 (to X.Z.), 31930013 (to X.Z.), and 32270455 (to Z.G.); the CAS Project for Young Scientists in Basic Research (YSBR-097 to X.Z. and Z.G.); the China National Postdoctoral Program for Innovative T alents BX20220295 (to Z.G.); and the Bingzhi Postdoctoral Program of the Institute of Zoology, Chinese Academy of Sciences (to Z.G.). We thank X.W. and X.H.Z. for their help during the literature preparation and the Macaulay Library at the Cornell Lab of Ornithology for giving credits for the following bird photos: ML590680861, ML589976421, and ML583813531.
LITERATURE CITED 1. Fudickar AM, Alex EJ, Ellen D, Ketterson ED. 2021. Animal migration: an overview of one of nature’s great spectacles. Annu. Rev. Ecol. Evol. Syst. 52:479–97 2. Pulido F. 2007. The genetics and evolution of avian migration. BioScience 57:165–74 3. Liedvogel M, ˚ Akesson S, Staffan B. 2011. The genetics of migration on the move. Trends Ecol. Evol.
26:561–69 4. Kays R, Crofoot MC, Jetz W, Wikelski M. 2015. T errestrial animal tracking as an eye on life and planet.
Science 348:aaa2478 5. Menz MH, Scacco M, Bürki-Spycher HM, Williams HJ, Reynolds DR, et al. 2022. Individual tracking reveals long-distance flight-path control in a nocturnally migrating moth. Science 377:764–68 6. Liedvogel M. 2019. Genetics of animal and bird migration. In Encyclopedia of Animal Behavior, ed.
JC Choe, pp. 323–30. New York/London: Academic 7. Newton I, Dale L. 1996. Relationship between migration and latitude among west European birds.
J. Anim. Ecol. 65:137–46 8. Flack A, Fiedler W, Blas J, Pokrovsky I, Kaatz M, et al. 2016. Costs of migratory decisions: a comparison across eight white stork populations. Sci. Adv. 2:e1500931 9. Klaassen RH,Hake M,Strandberg R,Koks BJ,Trierweiler C,et al.2014.When and where does mortality occur in migratory birds? Direct evidence from long-term satellite tracking of raptors. J. Anim. Ecol.
83:176–84 10. Somveille M, Rodrigues AS, Manica A. 2018. Energy efficiency drives the global seasonal distribution of birds. Nat. Ecol. Evol. 2:962–69 11. Soriano-Redondo A, Gutiérrez JS, Hodgson D, Bearhop S. 2020. Migrant birds and mammals live faster than residents. Nat. Commun. 11:5719 12. Alerstam T, Hedenström A, ˚ Akesson S

57 132. Milá B, Smith TB, Wayne RK. 2006. Postglacial population expansion drives the evolution of long-distance migration in a songbird. Evolution 60:2403–9 133. Somveille M, Wikelski M, Beyer RM, Rodrigues AS, Manica A, et al. 2020. Simulation-based reconstruction of global bird migration over the past 50,000 years. Nat. Commun. 11:801 134. Ponti R, Arcones A, Ferrer X, Vieites DR. 2020. Lack of evidence of a Pleistocene migratory switch in current bird long-distance migrants between Eurasia and Africa. J. Biogeogr. 47:1564–73 135. Neukom R, Steiger N, Gómez-Navarro JJ, Wang J, Werner JP. 2019. No evidence for globally coherent warm and cold periods over the preindustrial Common Era. Nature 571:550–54 136. Jonzén N, Lindén A, Ergon T, Knudsen E, Vik JO, et al. 2006. Rapid advance of spring arrival dates in long-distance migratory birds. Science 312:1959–61 137. Horton KG, La Sorte FA, Sheldon D, Lin TY, Winner K, et al. 2020. Phenology of nocturnal avian migration has shifted at the continental scale. Nat. Clim. Change 10:63–68 138. Lameris TK, Scholten I, Bauer S, Cobben MM, Ens BJ, et al. 2017. Potential for an Arctic-breeding migratory bird to adjust spring migration phenology to Arctic amplification. Glob. Change Biol. 23:4058– 67 139. Zurell D, Graham CH, Gallien L, Thuiller W, Zimmermann NE. 2018. Long-distance migratory birds threatened by multiple independent risks from global change. Nat. Clim. Change 8:992–96 42 Gu • Dixon • Zhan Annu. Rev. Anim. Biosci. 2024.12:21-43. Downloaded from www.annualreviews.org Access provided by 2a00:f29:2c8:8d99:4961:b044:a192:dd0d on 02/26/24. See copyright for approved use. 140. Dufour D, Christophe DF, Paul DV, Frédéric J, Maya G, et al. 2021. A new westward migration route in an Asian passerine bird. Curr. Biol. 31:5590–96 141. Schmaljohann H, Both C. 2017. The limits of modifying migration speed to adjust to climate change.
Nat. Clim. Change 7:573–76 142. Radchuk V,Reed T,T eplitsky C,van de Pol M,Charmantier A,et al.2019.Adaptive responses of animals to climate change are most likely insufficient. Nat. Commun. 10:3109 143. Scotese C. 2016. PALEOMAP PaleoAtlas for GPlates and the PaleoData Plotter Program. Rep., PALEOMAP Proj. http://www.earthbyte.org/paleomap-paleoatlas-for-gplates/ www.annualreviews.org • Genetics and Evolution of Bird Migration 43 Annu. Rev. Anim. Biosci. 2024.12:21-43. Downloaded from www.annualreviews.org Access provided by 2a00:f29:2c8:8d99:4961:b044:a192:dd0d on 02/26/24. See copyright for approved use. Annual Review of Animal Biosciences Volume 12, 2024 Contents How Fish Population Genomics Can Promote Sustainable Fisheries: A Road Map Leif Andersson, Dorte Bekkevold, Florian Berg, Edward D. Farrell, Sabine Felkel, Mafalda S. Ferreira, Angela P. Fuentes-Pardo, Jake Goodall, and Mats Pettersson p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p 1 Genetics and Evolution of Bird Migration Zhongru Gu, Andrew Dixon, and Xiangjiang Zhan p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p p

[2] Query: bird migration genetic adaptations climate change
Title: Genetics and Evolution of Bird Migration
URL: https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239
Snippet: )).

Subsequently, Zink & Gardner ([129](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#right-ref-B129)) raised concerns about the above study ([128](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#right-ref-B128)) for not considering the unequal living conditions at various latitudes when studying the evolution of migration. Additionally, studies using ancestral state reconstruction approaches also face challenges in interpreting trait evolution, as demonstrated by Ponti et al. ([130](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#right-ref-B130)), who used Sylvia warblers to study the evolution of migration and assess the impact of different elements such as branch length estimation, trait coding, statistical framework, and taxon sampling. Despite these challenges, with the increasing number (N = 363) of bird genomes being sequenced ([131](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#right-ref-B131)) and the emergence of more comprehensive statistical models, studying the origin and evolution of bird migration from a systematic genomics perspective seems to be very promising in the future.

4.3. Environmental Changes and Ongoing Evolution of Bird Migration
Migratory birds have been shown to be sensitive to climate change, and research has demonstrated that past climate change had already influenced the evolution of bird migration ([132](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#right-ref-B132)). Recent advancements in understanding the response of bird migration to changing climates have been made ([Figure 2 c](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#f2)), including the suggestion that birds can either switch off their migratory behavior or maintain their migration while shifting their range in response to glaciations ([129](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#right-ref-B129), [133](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#right-ref-B133), [134](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#right-ref-B134)). Genome-based methods have also provided strong support for reconstructing past demography and deepening our understanding of bird migration (e.g., [43](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#right-ref-B43), [47](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#right-ref-B47)).

However, we are currently in the Anthropocene era, a period marked by rapid climate change, such as the unprecedented rising of global temperature, due mainly to human activities ([135](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#right-ref-B135)). As temperatures continue to rise, many bird species have been found to change their migratory strategies, with some birds advancing their migration time ([136](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#right-ref-B136), [137](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#right-ref-B137)), potentially resulting in reduced breeding success rates ([138](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#right-ref-B138)). Additionally, rising temperatures can alter the migration distance of birds, with long-distance migratory birds being at risk of losing breeding and wintering habitats, as well as facing longer migration distances, due to intensified global warming ([139](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#right-ref-B139)).

Moreover, the changes in climate could also cause birds to evolve new migration routes ([Figure 2 c](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#f2)). One example is Richard's pip

it (Anthus richardi), a migratory songbird that breeds in the Siberian grasslands and winters in Southeast Asia. Dufour et al. ([140](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#right-ref-B140)) found that the species has become a regular autumn and winter visitor to western Europe only recently, likely because of an increase of wintering niche suitability due to climate change.

Despite some migratory bird species being able to adapt or respond quickly to climate change, it may be insufficient to mitigate the adverse impacts of climate change on their migratory patterns. For instance, Schmaljohann & Both ([141](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#right-ref-B141)) conducted a review of 49 tracking studies and quantified the potential range of adjusting spring arrival dates through modifying migration speeds. They found that among-individual variation in migration speed was determined mainly by the relatively short stopover duration. By assuming that this population response reflects individual phenotypic plasticity, they calculated the potential for phenotypic plasticity to speed up migration by reducing stopover duration. However, the flexibility in the major determinant of migration duration seems insufficient to adjust to ongoing climate change and is unlikely to explain some of the observed arrival advancements in long-distance migrants ([141](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#right-ref-B141)). Similarly, a meta-analysis of 71 bird studies showed that species with adaptive phenotypic responses may be evolving too slowly to keep pace with global climate change ([142](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#right-ref-B142)).

[5. CONCLUDING REMARKS AND FUTURE PROSPECTS](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239)

Go to section...

*   [TOP](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#top-1)
*   [ABSTRACT](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#abstract-1)
*   [INTRODUCTION](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#sec1)
*   [MIGRATION: AN EVOLVED COMPLEX BEHAVIOR IN BIRDS](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#sec2)
*   [GENETICS OF BIRD MIGRATION](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#sec3)
*   [EVOLUTION OF BIRD MIGRATION](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#sec4)
*   [CONCLUDING REMARKS AND FUTURE PROSPECTS](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#sec5)
*   [disclosure statement](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#sec6)
*   [acknowledgments](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#ack1)
*   [literature cited](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#sec7)

The study of the genetics and evolution of bird migration is a constantly evolving field that has witnessed significant advances in recent years. Looking ahead, there are several promising areas for future research in this enigmatic field.

5.1. Molecular Mechanisms of Migration
Although past studies have shown that genetics plays an important role in migratory strategies, we still have much to learn about the specific genes, gene interactions, and molecular pathways involved. To gain a deeper understanding of molecular mechanisms of migration, future research should use omics technologies to study the genetic basis across a wide range of bird species. By comparing genomes of different bird species or populations with varied migratory strategies, researchers can identify target genes and genetic variations associated

 with migration and investigate their evolutionary origins. This approach has already yielded valuable insights into the genetic basis of migration and is highly likely to continue to contribute to our understanding of bird migration in the future.

5.2. Elaborate Functional Experiments
Previous studies using various methods such as candidate genes, genomics, transcriptomics, and epigenetics have identified numerous genetic variations relevant to migration behavior; most, however, still lack evidence of functional significance. In addition, to our knowledge, there is still no implementation of gene-editing technology in the study of migratory birds. Therefore, more elaborate functional experiments are needed to fully understand the direct effects of these identified genetic loci on bird migration. Meanwhile, it is also important to evaluate and control the potential risks associated with genetically modified organisms once they are released to the wild.

5.3. Evolutionary Origin of Bird Migration
Studying the evolutionary origin of bird migration is an area of active research. The use of phylogenetic and phylogeographic approaches has spurred significant progress in this field, but many important questions remain unexplored (e.g., Where are the evolutionary origins of bird migration?). With more and more bird genomes being sequenced, systematic tests on various hypotheses using phylogenomic-based methods, along with reconstructed long-term paleoclimate or geochemistry data, could facilitate our understanding of the evolution of bird migration.

5.4. Migratory Strategies in Response to Climate Change
The impacts of climate change on migratory birds are a significant concern, as changing climate conditions can disrupt migratory patterns and threaten the survival of these species. To better understand how migratory birds respond to climate change, future research could investigate the evolved strategies of these birds in response to such changes and identify adaptive genes that may hinder or facilitate their future survival. This knowledge will be key to developing target strategies for mitigating the impacts of climate change on migratory birds.

In summary, although the prospect is promising, research on the genetics and evolution of bird migration is still as full of challenges as ever. One such challenge is how to effectively process and analyze large amounts of data, especially when more and more whole-genome and real-time tracking data are produced. The solution is far beyond classical fields such as animal behavior or genetics, but luckily, interdisciplinary collaborations have already begun to form between researchers from different fields, such as mathematics, physics, and biology.

[disclosure statement](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239)

Go to section...

*   [TOP](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#top-1)
*   [ABSTRACT](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#abstract-1)
*   [INTRODUCTION](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#sec1)
*   [MIGRATION: AN EVOLVED COMPLEX BEHAVIOR IN BIRDS](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#sec2)
*   [GENETICS OF BIRD MIGRATION](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#sec3)
*   [EVOLUTION OF BIRD MIGRATION](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#sec4)
*   [CONCLUDING REMARKS AND FUTURE PROSPECTS](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#sec5)
*   [disclosure statement](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#sec6)
*   [acknowledgments](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#ack1)
*   [literature cited](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#sec7)

The authors are not aware of any affiliations, memberships, funding, or financial holdings that might be perceived as affecting the objectivity of this review.

[acknowledgments](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239)

Go to section...

2021.  A new westward migration route in an Asian passerine bird. Curr. Biol.31:5590–96  [[Google Scholar]](http://scholar.google.com/scholar_lookup?title=A+new+westward+migration+route+in+an+Asian+passerine+bird&author=D+Dufour&author=DF+Christophe&author=DV+Paul&author=J+Fr%C3%A9d%C3%A9ric&author=G+Maya&journal=Curr.+Biol.&volume=31&pages=5590-96&publication_year=2021&)
141.   [](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239)141. Schmaljohann H, Both C.2017.  The limits of modifying migration speed to adjust to climate change. Nat. Clim. Change 7:573–76  [[Google Scholar]](http://scholar.google.com/scholar_lookup?title=The+limits+of+modifying+migration+speed+to+adjust+to+climate+change&author=H+Schmaljohann&author=C.+Both&journal=Nat.+Clim.+Change&volume=7&pages=573-76&publication_year=2017&)
142.   [](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239)142. Radchuk V, Reed T, Teplitsky C, van de Pol M, Charmantier A et al.2019.  Adaptive responses of animals to climate change are most likely insufficient. Nat. Commun.10:3109  [[Google Scholar]](http://scholar.google.com/scholar_lookup?title=Adaptive+responses+of+animals+to+climate+change+are+most+likely+insufficient&author=V+Radchuk&author=T+Reed&author=C+Teplitsky&author=M+van+de+Pol&author=A+Charmantier&journal=Nat.+Commun.&volume=10&pages=3109&publication_year=2019&)
143.   [](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239)143. Scotese C.2016. PALEOMAP PaleoAtlas for GPlates and the PaleoData Plotter Program. Rep. PALEOMAP Proj. [http://www.earthbyte.org/paleomap-paleoatlas-for-gplates/](http://www.earthbyte.org/paleomap-paleoatlas-for-gplates/)  [[Google Scholar]](http://scholar.google.com/scholar_lookup?title=PALEOMAP+PaleoAtlas+for+GPlates+and+the+PaleoData+Plotter+Program&author=C.+Scotese&publication_year=2016&)

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[3] Query: bird migration genetic adaptations climate change
Title: Bird migration - Wikipedia
URL: https://en.wikipedia.org/wiki/Bird_migration
Snippet: -96)[[97]](#cite_note-97) Apart from physiological adaptations, migration sometimes requires behavioural changes such as flying in flocks to reduce the energy used in migration or the risk of predation.[[98]](#cite_note-98)

## Evolutionary and ecological factors

Migration in birds is highly labile and is believed to have developed independently in many avian lineages.[[99]](#cite_note-99) While it is agreed that the behavioural and physiological adaptations necessary for migration are under genetic control, some authors have argued that no genetic change is necessary for migratory behaviour to develop in a sedentary species because the genetic framework for migratory behaviour exists in nearly all avian lineages.[[100]](#cite_note-100) This explains the rapid appearance of migratory behaviour after the most recent glacial maximum.[[101]](#cite_note-101)

Theoretical analyses show that detours that increase flight distance by up to 20% will often be adaptive on [aerodynamic](/wiki/Aerodynamics "Aerodynamics") grounds – a bird that loads itself with food to cross a long barrier flies less efficiently. However some species show circuitous migratory routes that reflect historical range expansions and are far from optimal in ecological terms. An example is the migration of continental populations of [Swainson's thrush](/wiki/Swainson%27s_thrush "Swainson's thrush") *Catharus ustulatus*, which fly far east across [North America](/wiki/North_America "North America") before turning south via [Florida](/wiki/Florida "Florida") to reach northern [South America](/wiki/South_America "South America"); this route is believed to be the consequence of a range expansion that occurred about 10,000 years ago. Detours may also be caused by differential wind conditions, predation risk, or other factors.[[102]](#cite_note-102)

### Climate change

![](//upload.wikimedia.org/wikipedia/commons/thumb/c/c9/Saalfeld_2021_bird_phenology.png/250px-Saalfeld_2021_bird_phenology.png)

Large scale [climatic changes](/wiki/Global_warming "Global warming") are expected to have an effect on the timing of migration. Studies have shown a variety of effects including timing changes in migration,[[104]](#cite_note-104) breeding[[105]](#cite_note-105) as well as population declines.[[106]](#cite_note-106)[[107]](#cite_note-107)

Bird migration is generally synchronised to take advantage of seasonal resources. For example, there is a strong link between seasonal migration and vegetation greenness in North America.[[108]](#cite_note-108) Climate-induced shifts in the [phenology](/wiki/Phenology "Phenology") of seasonal resource availability can cause mismatches between the timing of increased resource availability and important life-history events such as migration and breeding (aka [phenological mismatch](/wiki/Phenological_mismatch "Phenological mismatch") or phenological asynchrony).[[109]](#cite_note-:03-109) These mismatches between the timing of resource availability and when organisms need additional resources may impact species' [fitness](/wiki/Fitness_(biology) "Fitness (biology)"), as described by the [match-mismatch hypothesis](/wiki/Match/mismatch "Match/mismatch").[[110]](#cite_note-110)

In birds, individuals may use local temperature as a cue for migration. Changing temperature patterns due to climate change can result in [population](/wiki/Population_(biology) "Population (biology)")-level shifts in migration phenology.[[111]](#cite_note-111) Such shifts in the timing of migration of hundreds of species are already detectable at the continental scale.[[112]](#cite_note-112) While phenological mismatches appear to be more pronounced in long-distance migrants,[[109]](#cite_note-:03-109) certain species traits such as a [generalist diet](/wiki/Generalist_and_specialist_species "Generalist and specialist species") may help some species avoid more severe consequences of mismatches.[[113]](#cite_note-113)

## Ecological effects

The migration of birds aids the movement of other species, including those of [ectoparasites](/wiki/Ectoparasite "Ectoparasite") such as [ticks](/wiki/Ticks "Ticks") and [lice](/wiki/Lice "Lice"),[[114]](#cite_note-114) which in turn may carry [micro-organisms](/wiki/Micro-organism "Micro-organism") including those of concern to human health. Due to the global spread of [avian

[4] Query: bird migration genetic adaptations climate change
Title: Conservation of North American migratory birds: insights from ...
URL: https://ace-eco.org/vol19/iss2/art13
Snippet:  resources, depending on flight duration, weather conditions, and migration strategy (e.g., brief versus extended flights, flapping versus soaring flight [Wikelski et al. 2003, Bowlin et al. 2005, Weber 2009, Soriano-Redondo et al. 2023]). These physiological requirements of migration can aid in identifying critical areas for conserving or enhancing stopover sites and inform management to increase the availability of high-quality food and other resources (Seewagen et al. 2011, Smith et al. 2015, Bayly et al. 2016, Gómez et al. 2017).

The importance of specific stopover sites may depend on the migration ecology of focal species. For example, tracking data from many songbirds and shorebirds show that these species often migrate via several extensive movements (i.e., “jumps”) and may benefit from the conservation of strategically located high-quality stopover sites in areas used immediately before initiating and after completing such flights (Piersma 1987, Skagen and Knopf 1994, Warnock 2010). However, focusing conservation efforts on a few stopover sites may be impractical and ineffective for species like American Woodcock that make many, shorter-distance movements to complete migration and rely on a network of sites in close proximity to sustain migration (i.e., “hops” [Piersma 1987, Moore et al. 2021]).

Similarly, whether species migrate primarily diurnally (e.g., soaring raptors, swallows, cranes [Beauchamp 2011]) or nocturnally (most songbirds [Cooper et al. 2023]), and how birds move within those periods may be important for developing targeted conservation strategies that minimize the effect of anthropogenic factors such as wind energy development (potentially a risk for diurnal soaring raptors [Katzner et al. 2012]) or ALAN (primarily an issue for nocturnally migrating songbirds [Evans Ogden 2002, Spoelstra and Visser 2013, Van Doren et al. 2017, McLaren et al. 2018]). Other species-specific characteristics of migration may be critical for informing conservation decisions (e.g., flight altitude to inform the location of wind energy development [Katzner et al. 2012, Cohen et al. 2022]).

### Understanding proximate drivers of migration can inform conservation (why)

Whether migratory behavior is innate or socially inherited can affect subsequent conservation decisions. For obligate migrants where migration is presumed to be genetically controlled (e.g., songbirds [Toews et al. 2019, Justen and Delmore 2022]), migration timing appears to be linked to photoperiodic cues that may become disentangled from changing phenological patterns, leading to phenological mismatch (Both et al. 2006, 2010, Youngflesh et al. 2021, Connare and Islam 2022, Robertson et al. 2024). For species that migrate more slowly, arrive earlier on breeding areas, or overwinter farther north, migratory timing may be more flexible and responsive to earlier spring onset resulting from climate change because their migration strategy generally tracks local environmental conditions (Halupka and Halupka 2017, Youngflesh et al. 2021).

Within species, different cohorts may be affected differently by climate change. In many migratory North American bird species, males arrive at breeding sites days to weeks before females (i.e., protandry [Morbey and Ydenberg 2001]). However, decades of banding data suggest that the gap between male and female arrival at breeding grounds has widened because males arrive at breeding sites earlier in response to changes in spring phenology (Neate-Clegg and Tingley 2023). The mechanisms underlying sex-based plasticity in adaptation to climate change are unclear, but the increasing mismatch between arrival of males and females on breeding areas could cause populations to decline (Neate-Clegg and Tingley 2023). In some cases, loss of migratory behavior may be an adaptive response to an erosion of the potential benefits of migration, which could allow for population persistence but eliminate the ecological functions of migration (de Zoeten and Pulido 2020).

The capacity of species to adapt to changing conditions via evolutionary pathways may also affect their persistence under future conditions and may be affected by the rate at which conditions change (with slower rates of change assumed to be more conducive to adaptation [Botero et al. 2015]). Capacity for adaptation is partially dependent on standing genetic variation (Both and Visser 2001, Webster et al. 2002), and individuals that possess traits that are extreme today (e.g., an individual that initiates migration early relative to the rest of
</search_results>

[Assistant]
Bird species adjust their migration routes in response to climate change and habitat loss through a combination of genetic and physiological adaptations. Key findings include:

- **Genetic Adaptations**:
  - Genetics plays a significant role in migratory strategies, with specific genes and genetic variations influencing migration behavior.
  - Studies suggest that genetic variation, such as in the VPS13A gene, is linked to migration in some songbirds.
  - The genetic framework for migratory behavior exists in many avian lineages, allowing for rapid development of migration in sedentary species when needed.
  - Genome-based methods are being used to identify target genes and genetic variations associated with migration and their evolutionary origins.

- **Physiological Adaptations**:
  - Birds adjust migration timing and speed in response to climate change, with some species advancing their migration to align with earlier springs.
  - Stopover duration is a major determinant of migration speed, and reducing it can help birds adjust to climate change, though this flexibility may be insufficient for long-distance migrants.
  - Birds use local temperature as a cue for migration, and changes in temperature patterns due to climate change can shift migration phenology at the population level.

- **Behavioral and Ecological Responses**:
  - Some species evolve new migration routes in response to climate change, such as the Richard’s pipit, which has recently begun migrating to western Europe due to increased wintering niche suitability.
  - Birds may switch off migratory behavior or shift their range in response to habitat loss and climate change, which can be an adaptive response to reduce the costs of migration.
  - Conservation strategies must consider species-specific migration patterns, such as whether birds migrate via "jumps" or "hops," and whether they migrate diurnally or nocturnally.

- **Challenges and Future Research**:
  - While some species can adapt to climate change, the rate of adaptation may be too slow to keep pace with rapid environmental changes.
  - Functional experiments and gene-editing technologies are needed to understand the direct effects of genetic loci on migration.
  - Interdisciplinary approaches are essential to process and analyze large datasets, including whole-genome and real-time tracking data, to better understand and mitigate the impacts of climate change on migratory birds.


[System] Compress the provided search results for the current sub-query. Only Extract key information that is relevant to the overall research question. Write plain text only.

[User]
<research_question>
What specific genetic or physiological adaptations enable certain bird species to adjust their migration routes in response to climate change or habitat loss?
</research_question>

<search_results>
[1] Query: how do birds adjust migration routes with climate change
Title: Migratory birds: how they survive in an anthropogenic world
URL: https://sciencemediacentre.es/en/migratory-birds-how-they-survive-anthropogenic-world
Snippet:  has a direct impact on the functioning of ecosystems globally.

Pérez-Tris adds that changes in the migratory patterns of species affect the predators that consume them, as well as the prey of the migratory birds themselves. The researcher explains that bird migration is also key for organisms that cannot move, citing plant pollination as an example: ‘Seeds can be efficiently dispersed by the huge numbers of migratory birds that feed on their fruits to obtain energy for their journey, and parasites and other pathogens also move on an intercontinental scale by taking advantage of migratory flows.’

What are the main threats they face?

Although it depends greatly on the species involved, these birds share several threats: ‘Processes related to global change and the widespread modification of an increasingly anthropic environment,’ says Pérez-Tris, adding that these impacts include not only those derived from climate change, such as the drying up of wetlands, but also others such as agricultural intensification and poorly managed hunting.

The UCM professor explains that migratory birds depend on the good conservation status of different places, which sometimes span global contexts. This is a threat in itself, as their conservation ‘requires coordination between different administrations, often from different countries’.

For his part, Camacho highlights the loss and deterioration of breeding, resting and feeding sites for migratory birds as a result of urbanisation, agriculture, deforestation and climate change. The latter factor ‘alters the degree of synchronisation of birds with other species with which they interact’.

One of the phenomena that puts these species at risk is light pollution. A [study](https://www.sciencedirect.com/science/article/pii/S0169534722003329?via%3Dihub) published in *Trends in Ecology & Evolution* reports that light pollution can intensify the consequences of environmental pollution during migration and even afterwards. These effects cause changes in the behaviour and physiology of the affected populations, hindering their survival and reproductive success during the breeding season.

How is climate change affecting you?

‘In very general terms, they find it difficult to adjust their life cycle to new conditions that change too quickly,’ summarises Pérez-Tris. The UCM professor explains that it is difficult to generalise when talking about effects, since climate change, despite being a global phenomenon, manifests itself in particular responses ’both in environments and in the organisms that depend on them.’

One of the problems facing migratory birds is adjusting their migration dates to the new temporal distribution of the resources they need. ‘If they arrive at their destinations before or after the peak availability of food, they may encounter serious difficulties in meeting their energy needs,’ says Camacho.

The decline in the quality of the breeding areas to which these species migrate has also had a negative impact on the demographics of some populations.

Furthermore, changes in their reference environments are not the only reasons why migratory birds have had to modify their cyclical migrations. A [research study](https://www.pnas.org/doi/10.1073/pnas.2311146121) published in 2024 in PNAS reports that many species have changed the timing of their migration in order to adapt to earlier springs.

Leal points out that climate change also has specific effects that affect food availability, with phenomena such as torrential rains, sudden drops in temperature and droughts.

How are you adapting to ongoing global changes?

Their adaptation to global changes has been uneven across species: ‘While some seem to have adapted quickly by changing their migration schedules, others have kept them unchanged,’ Pérez-Tris points out.

A [research study](https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecy.3938) published in the journal *Ecology* concludes that although some migratory bird species are able to delay their departure—to cope with factors such as drought or habitat degradation—and compensate for this time by accelerating their pace along their routes, this alteration has a direct negative impact on their survival.

In addition, there are species that are forced to change their migratory destinations. This is reported in a [study](https://www.pnas.org/doi/full/10.1073/pnas.2000299117#sec-2) of 32 bird species in eastern North America, published in PNAS: the birds analysed had shifted their migration destinations by almost half a degree of latitude to the north.

In our environment, Tellería explains that fewer and fewer birds are travelling to our country from northern Europe. ‘There are species that are no longer migrating to our fields to spend the winter,’ he says.

However, the scientific community has not yet found an explanation for the variable adaptation of different species to global changes, or even for the fact that some of them are not changing their migratory routes. ‘We cannot explain why some species choose conservative routes at the cost of huge detours and others rapidly develop completely new migratory programmes,’

[2] Query: how do birds adjust migration routes with climate change
Title: Bird migration - Wikipedia
URL: https://en.wikipedia.org/wiki/Bird_migration
Snippet: -96)[[97]](#cite_note-97) Apart from physiological adaptations, migration sometimes requires behavioural changes such as flying in flocks to reduce the energy used in migration or the risk of predation.[[98]](#cite_note-98)

## Evolutionary and ecological factors

Migration in birds is highly labile and is believed to have developed independently in many avian lineages.[[99]](#cite_note-99) While it is agreed that the behavioural and physiological adaptations necessary for migration are under genetic control, some authors have argued that no genetic change is necessary for migratory behaviour to develop in a sedentary species because the genetic framework for migratory behaviour exists in nearly all avian lineages.[[100]](#cite_note-100) This explains the rapid appearance of migratory behaviour after the most recent glacial maximum.[[101]](#cite_note-101)

Theoretical analyses show that detours that increase flight distance by up to 20% will often be adaptive on [aerodynamic](/wiki/Aerodynamics "Aerodynamics") grounds – a bird that loads itself with food to cross a long barrier flies less efficiently. However some species show circuitous migratory routes that reflect historical range expansions and are far from optimal in ecological terms. An example is the migration of continental populations of [Swainson's thrush](/wiki/Swainson%27s_thrush "Swainson's thrush") *Catharus ustulatus*, which fly far east across [North America](/wiki/North_America "North America") before turning south via [Florida](/wiki/Florida "Florida") to reach northern [South America](/wiki/South_America "South America"); this route is believed to be the consequence of a range expansion that occurred about 10,000 years ago. Detours may also be caused by differential wind conditions, predation risk, or other factors.[[102]](#cite_note-102)

### Climate change

![](//upload.wikimedia.org/wikipedia/commons/thumb/c/c9/Saalfeld_2021_bird_phenology.png/250px-Saalfeld_2021_bird_phenology.png)

Large scale [climatic changes](/wiki/Global_warming "Global warming") are expected to have an effect on the timing of migration. Studies have shown a variety of effects including timing changes in migration,[[104]](#cite_note-104) breeding[[105]](#cite_note-105) as well as population declines.[[106]](#cite_note-106)[[107]](#cite_note-107)

Bird migration is generally synchronised to take advantage of seasonal resources. For example, there is a strong link between seasonal migration and vegetation greenness in North America.[[108]](#cite_note-108) Climate-induced shifts in the [phenology](/wiki/Phenology "Phenology") of seasonal resource availability can cause mismatches between the timing of increased resource availability and important life-history events such as migration and breeding (aka [phenological mismatch](/wiki/Phenological_mismatch "Phenological mismatch") or phenological asynchrony).[[109]](#cite_note-:03-109) These mismatches between the timing of resource availability and when organisms need additional resources may impact species' [fitness](/wiki/Fitness_(biology) "Fitness (biology)"), as described by the [match-mismatch hypothesis](/wiki/Match/mismatch "Match/mismatch").[[110]](#cite_note-110)

In birds, individuals may use local temperature as a cue for migration. Changing temperature patterns due to climate change can result in [population](/wiki/Population_(biology) "Population (biology)")-level shifts in migration phenology.[[111]](#cite_note-111) Such shifts in the timing of migration of hundreds of species are already detectable at the continental scale.[[112]](#cite_note-112) While phenological mismatches appear to be more pronounced in long-distance migrants,[[109]](#cite_note-:03-109) certain species traits such as a [generalist diet](/wiki/Generalist_and_specialist_species "Generalist and specialist species") may help some species avoid more severe consequences of mismatches.[[113]](#cite_note-113)

## Ecological effects

The migration of birds aids the movement of other species, including those of [ectoparasites](/wiki/Ectoparasite "Ectoparasite") such as [ticks](/wiki/Ticks "Ticks") and [lice](/wiki/Lice "Lice"),[[114]](#cite_note-114) which in turn may carry [micro-organisms](/wiki/Micro-organism "Micro-organism") including those of concern to human health. Due to the global spread of [avian

[3] Query: how do birds adjust migration routes with climate change
Title: Climate‐related drivers of migratory bird health in the south‐central USA
URL: https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389
Snippet:  species and spans their inbound and outbound migration routes (exemplified by black lines and arrows) between their northern breeding grounds and their southern wintering areas. The domain of the South Central Climate Adaptation Science Center (CASC) is shaded in blue. Figure adapted from BirdLife International ([2010](https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389#brv70000-bib-0016)) (accessed 25 July 2024). Copyrighted; used with permission.

We acknowledge that the scope of work of wildlife managers limits them from tracking study subjects' health and climate change impacts outside of their jurisdiction. New data analytics capabilities (e.g. artificial intelligence, machine learning), however, can support innovations in migratory bird management that infuse dispersed data and knowledge about climate change and health stressors into place‐based contexts useful for management decisions.

### Climate variability and change

(3)
Climate is the statistical representation of all weather observed in a particular area over an extended period of time (typically 30 years or longer), and anthropogenic climate change has been detected since the start of the Industrial Revolution. Future climate change is projected using global climate models (GCMs) that adequately represent the physics of the atmosphere and, in more recent GCMs, its coupling to physical processes in the ocean, cryosphere, and biosphere (IPCC,[2021](https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389#brv70000-bib-0060)). These numerical models are forced by broad‐scale inputs (e.g. concentrations of various greenhouse gases) across different scenarios that represent possible future trajectories of human development and their impacts on the radiative energy input into Earth's atmosphere [e.g. representative concentration pathway (RCP)4.5 adds 4.5 Wm−2 of radiative forcing by 2100 relative to pre‐industrial forcing]. GCMs output daily or sub‐daily data that are aggregated into seasonal or annual products (e.g. total annual precipitation, winter minimum temperature).

The impacts of climate change, however, tend to be most evident at shorter timescales during climate extremes, as manifested by the weather – the atmospheric condition at a particular place and time. Hence, climatologists examine impacts not only from long‐term trends but also from extremes, which also can be extracted from GCM output. Lessons learned from extreme events are useful when those events (e.g. droughts, heavy rainfall, heatwaves) are projected to become more frequent with climate change. This review follows that perspective, highlighting climate change signals that manifest as long‐term changes (trends) or as climate extremes.

We categorise results from peer‐reviewed literature into three main sections: breeding period, wintering (non‐breeding) period, and migration, each of which is subdivided by effects on key health determinants according to the framework.

## [](https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389)BREEDING PERIOD

II.
During the breeding season, birds may build a nest, secure a mate, defend a territory, raise their young, and complete a moult. They may change habitats for different life stages, for example to protect post‐fledgling juveniles better. Most migratory birds will arrive at their breeding grounds several weeks before they start laying their eggs, allowing them time to find resources, recover from their flight, build nests, and find a mate. Earlier arrivers generally occupy the best habitat, breed earlier than latecomers, and have the highest nest success rates but they also face higher risks (Newton,[2006](https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389#brv70000-bib-0102)), although for some species a combination of habitat quality and site fidelity is used to select territories (e.g. Lanyon & Thompson,[1986](https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389#brv70000-bib-0081)). Climate variability and change have negatively affected arrival, nesting, and reproduction in some populations, particularly when complicated by timing mismatches in the phenology of the populations and their food supplies (e.g. availability of seeds or flying insects). Behavioural plasticity – the ability of the bird to change its behaviour in response to environmental or other conditions – can aid some migratory birds in adapting to climate change.

### Direct impacts of climate change

(1)
Historical climate observations and future projections using GCMs indicate direct effects on near‐surface air temperatures across most land areas, including earlier arrival of spring warmth, later arrival of winter cold, warmer winters, warmer nights, and more days with seasonally extreme heat (IPCC,[2021](https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389#brv70000-bib-0060

 than during other seasons (Sillett & Holmes,[2002](https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389#brv70000-bib-0139); e.g. Carlisle _et al_.,[2009](https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389#brv70000-bib-0027)).

For many bird species, annual migration pathways are somewhat flexible depending on ground‐resource availability for stopovers and winds in the lower troposphere, presumably to reduce energy consumption, flight time, or both (Alerstam,[1979](https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389#brv70000-bib-0006); Marra _et al_.,[2005](https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389#brv70000-bib-0089)). Migratory birds that work to minimise their total flight time tend to refuel quickly at as few stopovers as possible, requiring high‐quality forage conditions at refuelling sites (Gómez _et al_.,[2017](https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389#brv70000-bib-0051)). Migrants that try to minimise their total energy expended during migration tend to reduce their fuel loads both in transit and at the stopover sites; thus, they avoid long stretches of unsuitable stopovers (e.g. seas, deserts) and stop more often to refuel than those minimising their total flight time (Gómez _et al_.,[2017](https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389#brv70000-bib-0051)).

Water, food, and shelter change during and after extreme climate events (e.g. drought), some of which are projected to become more frequent, more intense, or both under most climate scenarios (IPCC,[2021](https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389#brv70000-bib-0060)). Environmental conditions during spring migration have been shown to affect arrival timing and body condition on breeding grounds, population density, nest success, and clutch size (Carlisle _et al_.,[2009](https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389#brv70000-bib-0027)). Large‐scale, collaborative networks that track the migration of birds have helped to increase understanding of migratory patterns and the conditions that migrants experience; however, much is still unknown about weather impacts, food availability, parasites, diseases, and prey along migration routes (Bairlein,[2003](https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389#brv70000-bib-0014)).

### Direct impacts of climate change

(1)
#### Timing of migration

(a)
Warmer temperatures have been the most obvious climate change over the past several decades worldwide (IPCC,[2021](https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389#brv70000-bib-0060)) and will impact ecosystems for decades to come (Sala _et al_.,[2000](https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389#brv70000-bib-0129)). This warming has extended the growing season across most of North America, providing an opportunity for spring food supplies to become available earlier. Satellite remote‐sensing data indicate that ‘green‐up’ has shifted earlier for many high‐ and mid‐latitude locations (Badeck _et al_.,[2004](https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389#brv70000-bib-0013); Park, Jeong & Peñuelas,[2020](https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389#brv70000-bib-0108)).

Numerous studies have shown timing changes in species migrations associated with a warming climate. For spring migration, the timing of both passage over or arrival at high‐latitude locations is trending earlier overall, although annual variations (e.g. cold _versus_ warm spring) affect some migrating species (e.g. Smith, Mabey & Moore,[2009](https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389#brv70000-bib-0144)). For instance, Jorgensen & Brown ([2017](https://pmc.ncbi.nlm.nih.gov/articles/PMC12120389#brv70000-bib-0066)) determined that whooping cranes (_Grus americana_) that migrate between Wood Buffalo National Park, Alberta, Canada, and Aransas NWR, Texas, migrate an average of 22 days earlier in spring and 21 days

[4] Query: how do birds adjust migration routes with climate change
Title: Do first-time avian migrants know where they are going: the clock-and-compass concept today
URL: https://pmc.ncbi.nlm.nih.gov/articles/PMC12037376
Snippet: 37376#B57)) and West Africa ([Gatter, 1987a](https://pmc.ncbi.nlm.nih.gov/articles/PMC12037376#B44); [Gatter, 1987b](https://pmc.ncbi.nlm.nih.gov/articles/PMC12037376#B45)), suggest that the course change for most Palaearctic migrants occurs differently than what E. Gwinner and W. Wiltschko proposed for garden warblers. Apparently, the change in direction from a southwest to a southeast-east course does not occur after crossing the desert belt, but much later, along the northern coast of the Gulf of Guinea.

Studies have shown that migratory restlessness, typical of birds during the preparation for long flights, can be suppressed under experimental conditions. This is achieved by providing birds with unlimited food after a fasting period simulating the depletion of energy reserves during flight ([Biebach, 1985](https://pmc.ncbi.nlm.nih.gov/articles/PMC12037376#B20); [Gwinner et al., 1985](https://pmc.ncbi.nlm.nih.gov/articles/PMC12037376#B50); [Gwinner et al., 1988](https://pmc.ncbi.nlm.nih.gov/articles/PMC12037376#B51)). This scenario mimics natural conditions where birds reach suitable stopover sites, such as desert oases, to replenish their fat reserves. Notably, migratory restlessness disappears long before the birds achieve high fat levels and body mass. This suggests that the process of replenishing energy resources itself may serve as a signal for the temporary cessation of migratory behavior. Even when the total duration of such interruptions accounts for a significant proportion (25%–30%) of the autumn migration season, this does not lead to a proportional extension of the migration period. The migration season is not prolonged by the time spent at stopovers, despite the considerable time investment ([Gwinner et al., 1992](https://pmc.ncbi.nlm.nih.gov/articles/PMC12037376#B52); [Bairlein and Gwinner, 1994](https://pmc.ncbi.nlm.nih.gov/articles/PMC12037376#B9); [Gwinner, 1996](https://pmc.ncbi.nlm.nih.gov/articles/PMC12037376#B49)). If a similar situation occurs under natural conditions, and the duration of migration is indeed determined solely by an innate spatiotemporal program, some individuals may complete their migration prematurely, for instance, ending up in the middle of the Sahara. The consequences would most likely have been fatal.

Numerous studies on the impact of weather conditions on migration have confirmed that factors such as wind strength and direction significantly influence the migratory behavior of birds ([Alerstam, 1978](https://pmc.ncbi.nlm.nih.gov/articles/PMC12037376#B5); [Richardson, 1978](https://pmc.ncbi.nlm.nih.gov/articles/PMC12037376#B80); [Richardson, 1990](https://pmc.ncbi.nlm.nih.gov/articles/PMC12037376#B81); [Alerstam and Lindström, 1990](https://pmc.ncbi.nlm.nih.gov/articles/PMC12037376#B6); [Åkesson, 1993a](https://pmc.ncbi.nlm.nih.gov/articles/PMC12037376#B2)). In particular, unfavorable wind conditions can substantially increase energy expenditure and cause birds to deviate from their course. If young individuals during their first migration are unable to adjust their position and rely solely on innate directional knowledge and a temporal program, they risk failing to compensate for deviations and perishing.

Some published data suggest that at least in certain migratory bird species, young individuals undertaking their first migration possess if not a detailed navigational map, but at least a system of beacons enabling them to determine their position along the migration route at any given moment ([Fransson et al., 2001](https://pmc.ncbi.nlm.nih.gov/articles/PMC12037376#B41); [Thorup and Rabøl, 2007](https://pmc.ncbi.nlm.nih.gov/articles/PMC12037376#B93); [Gschweng et al., 2008](https://pmc.ncbi.nlm.nih.gov/articles/PMC12037376#B46); [Thorup et al., 2011](https://pmc.ncbi.nlm.nih.gov/articles/PMC12037376#B92); [2020](https://pmc.ncbi.nlm.nih.gov/articles/PMC12037376#B94)). Very impressive in this respect are the circumpolar movements of juvenile Northern giant petrels _Macronectes halli_ that are difficult to explain without assuming some kind of innate map ([de Grissac et al., 2016](https

[5] Query: how do birds adjust migration routes with climate change
Title: Magnetic information calibrates celestial cues during migration
URL: https://www.sciencedirect.com/science/article/pii/S0003347200915823
Snippet: Migratory birds use celestial and geomagnetic directional information to orient on their way between breeding and wintering areas.

[6] Query: how do birds adjust migration routes with climate change
Title: Climate Change Response: Bird Migrations
URL: https://www.climatecenter.pitt.edu/news/climate-change-response-bird-migrations
Snippet: ---

---

            In each study area, around one third of the bird species had alterations in the timing of migration. Both short and long-distance migrating species in South Carolina spent less time in their wintering grounds which is thought to be related to increasing MAT, where warmer temperatures result in greater food availability. Birds that traditionally migrate to wintering grounds for more food resources would not be pressed to migrate as soon because food has become increasingly available in their breeding grounds for longer periods of time. This is important because some ecosystems may depend on migrating bird species as an important predator or prey species, and a shift in that timing could have adverse effects on the ecosystem. Of 97 species analyzed in Alaska, 31 showed changes in migration patterns in response to increasing MAT. The bufflehead (a species of duck) saw the most extreme change of any bird in Alaska, arriving later and departing earlier over time. The late arrival and early departure is a trend that held for around 26% of species analyzed in Alaska. Of all the birds found in Maine, including the near-threatened semipalmated sandpiper, 31% of them stayed longer as temperatures increased. This species of sandpiper remained at its spring stopover longer when experiencing a higher minimum seasonal temperature which means it spent less time at its breeding and wintering grounds at which it may hold an important ecological role.

            Around a third of the bird species in the study are showing a phenological response to climate change, meaning that some birds are responding behaviorally to climate change and others are not. Intuitively, it might seem that a phenological response by the species to increasing MAT will be best for its survival, but it’ll take more observation and study to see if that’s the case. With increasing MAT scientists will need to closely observe species and determine if they do or do not respond phenologically to the changing climate as to not lose important members of our many different ecosystems.

---

**Sources**

Walther, G. R., Post, E., Convey, P., Menzel, A., Parmesan, C., Beebee, T. J., ... & Bairlein, F. (2002). Ecological responses to recent climate change. Nature, 416(6879), 389.

Zaifman, J., Shan, D., Ay, A., & Jimenez, A. G. (2017). Shifts in Bird Migration Timing in North American Long-Distance and Short-Distance Migrants Are Associated with Climate Change. International Journal of Zoology, 2017.

[7] Query: how do birds adjust migration routes with climate change
Title: [PDF] Genetics and Evolution of Bird Migration
URL: https://www.mbzraptorfund.org/wp-content/uploads/2025/05/Gu-et-al.-2024.-Genetics-evolution-of-bird-migration.-Ann.-Rev.-Anim.-Biosci.pdf
Snippet:  and deepening our understanding of bird migration (e.g., 43, 47).
However, we are currently in the Anthropocene era, a period marked by rapid climate change, such as the unprecedented rising of global temperature, due mainly to human activities (135). As temperatures continue to rise,many bird species have been found to change their migratory strate-gies, with some birds advancing their migration time (136, 137), potentially resulting in reduced breeding success rates (138). Additionally, rising temperatures can alter the migration distance of birds, with long-distance migratory birds being at risk of losing breeding and wintering habitats, as well as facing longer migration distances, due to intensified global warming (139).
Moreover, the changes in climate could also cause birds to evolve new migration routes (Figure 2c). One example is Richard’s pipit (Anthus richardi), a migratory songbird that breeds in the Siberian grasslands and winters in Southeast Asia. Dufour et al. (140) found that the species has become a regular autumn and winter visitor to western Europe only recently, likely because of an increase of wintering niche suitability due to climate change.
Despite some migratory bird species being able to adapt or respond quickly to climate change, it may be insufficient to mitigate the adverse impacts of climate change on their migratory patterns.
For instance, Schmaljohann & Both (141) conducted a review of 49 tracking studies and quantified the potential range of adjusting spring arrival dates through modifying migration speeds. They found that among-individual variation in migration speed was determined mainly by the relatively short stopover duration. By assuming that this population response reflects individual phenotypic plasticity, they calculated the potential for phenotypic plasticity to speed up migration by reducing stopover duration. However, the flexibility in the major determinant of migration duration seems insufficient to adjust to ongoing climate change and is unlikely to explain some of the observed arrival advancements in long-distance migrants (141). Similarly, a meta-analysis of 71 bird studies showed that species with adaptive phenotypic responses may be evolving too slowly to keep pace with global climate change (142).
www.annualreviews.org • Genetics and Evolution of Bird Migration 35 Annu. Rev. Anim. Biosci. 2024.12:21-43. Downloaded from www.annualreviews.org Access provided by 2a00:f29:2c8:8d99:4961:b044:a192:dd0d on 02/26/24. See copyright for approved use. 5. CONCLUDING REMARKS AND FUTURE PROSPECTS The study of the genetics and evolution of bird migration is a constantly evolving field that has witnessed significant advances in recent years. Looking ahead, there are several promising areas for future research in this enigmatic field.
5.1. Molecular Mechanisms of Migration Although past studies have shown that genetics plays an important role in migratory strategies, we still have much to learn about the specific genes, gene interactions, and molecular pathways involved. T o gain a deeper understanding of molecular mechanisms of migration, future research should use omics technologies to study the genetic basis across a wide range of bird species. By comparing genomes of different bird species or populations with varied migratory strategies, re-searchers can identify target genes and genetic variations associated with migration and investigate their evolutionary origins. This approach has already yielded valuable insights into the genetic basis of migration and is highly likely to continue to contribute to our understanding of bird migration in the future.
5.2. Elaborate Functional Experiments Previous studies using various methods such as candidate genes, genomics, transcriptomics, and epigenetics have identified numerous genetic variations relevant to migration behavior; most, however, still lack evidence of functional significance. In addition, to our knowledge, there is still no implementation of gene-editing technology in the study of migratory birds. Therefore, more elaborate functional experiments are needed to fully understand the direct effects of these identified genetic loci on bird migration. Meanwhile, it is also important to evaluate and control the potential risks associated with genetically modified organisms once they are released to the wild.
5.3. Evolutionary Origin of Bird Migration Studying the evolutionary origin of bird migration is an area of active research. The use of phylogenetic and phylogeographic approaches has spurred significant progress in this field, but many important questions remain unexplored (e.g., Where are the evolutionary origins of bird migration?). With more and more bird genomes being sequenced, systematic tests on various hy-potheses using phylogenomic-based methods, along with reconstructed long-term paleoclimate or geochemistry data, could facilitate our understanding of the evolution of bird migration.
5.4. Migratory Strategies in Response to Climate Change The impacts of climate change on migratory birds are a significant concern, as changing climate conditions can disrupt migratory patterns and threaten the survival of these

[8] Query: how do birds adjust migration routes with climate change
Title: Conservation of North American migratory birds: insights from ...
URL: https://ace-eco.org/vol19/iss2/art13
Snippet:  resources, depending on flight duration, weather conditions, and migration strategy (e.g., brief versus extended flights, flapping versus soaring flight [Wikelski et al. 2003, Bowlin et al. 2005, Weber 2009, Soriano-Redondo et al. 2023]). These physiological requirements of migration can aid in identifying critical areas for conserving or enhancing stopover sites and inform management to increase the availability of high-quality food and other resources (Seewagen et al. 2011, Smith et al. 2015, Bayly et al. 2016, Gómez et al. 2017).

The importance of specific stopover sites may depend on the migration ecology of focal species. For example, tracking data from many songbirds and shorebirds show that these species often migrate via several extensive movements (i.e., “jumps”) and may benefit from the conservation of strategically located high-quality stopover sites in areas used immediately before initiating and after completing such flights (Piersma 1987, Skagen and Knopf 1994, Warnock 2010). However, focusing conservation efforts on a few stopover sites may be impractical and ineffective for species like American Woodcock that make many, shorter-distance movements to complete migration and rely on a network of sites in close proximity to sustain migration (i.e., “hops” [Piersma 1987, Moore et al. 2021]).

Similarly, whether species migrate primarily diurnally (e.g., soaring raptors, swallows, cranes [Beauchamp 2011]) or nocturnally (most songbirds [Cooper et al. 2023]), and how birds move within those periods may be important for developing targeted conservation strategies that minimize the effect of anthropogenic factors such as wind energy development (potentially a risk for diurnal soaring raptors [Katzner et al. 2012]) or ALAN (primarily an issue for nocturnally migrating songbirds [Evans Ogden 2002, Spoelstra and Visser 2013, Van Doren et al. 2017, McLaren et al. 2018]). Other species-specific characteristics of migration may be critical for informing conservation decisions (e.g., flight altitude to inform the location of wind energy development [Katzner et al. 2012, Cohen et al. 2022]).

### Understanding proximate drivers of migration can inform conservation (why)

Whether migratory behavior is innate or socially inherited can affect subsequent conservation decisions. For obligate migrants where migration is presumed to be genetically controlled (e.g., songbirds [Toews et al. 2019, Justen and Delmore 2022]), migration timing appears to be linked to photoperiodic cues that may become disentangled from changing phenological patterns, leading to phenological mismatch (Both et al. 2006, 2010, Youngflesh et al. 2021, Connare and Islam 2022, Robertson et al. 2024). For species that migrate more slowly, arrive earlier on breeding areas, or overwinter farther north, migratory timing may be more flexible and responsive to earlier spring onset resulting from climate change because their migration strategy generally tracks local environmental conditions (Halupka and Halupka 2017, Youngflesh et al. 2021).

Within species, different cohorts may be affected differently by climate change. In many migratory North American bird species, males arrive at breeding sites days to weeks before females (i.e., protandry [Morbey and Ydenberg 2001]). However, decades of banding data suggest that the gap between male and female arrival at breeding grounds has widened because males arrive at breeding sites earlier in response to changes in spring phenology (Neate-Clegg and Tingley 2023). The mechanisms underlying sex-based plasticity in adaptation to climate change are unclear, but the increasing mismatch between arrival of males and females on breeding areas could cause populations to decline (Neate-Clegg and Tingley 2023). In some cases, loss of migratory behavior may be an adaptive response to an erosion of the potential benefits of migration, which could allow for population persistence but eliminate the ecological functions of migration (de Zoeten and Pulido 2020).

The capacity of species to adapt to changing conditions via evolutionary pathways may also affect their persistence under future conditions and may be affected by the rate at which conditions change (with slower rates of change assumed to be more conducive to adaptation [Botero et al. 2015]). Capacity for adaptation is partially dependent on standing genetic variation (Both and Visser 2001, Webster et al. 2002), and individuals that possess traits that are extreme today (e.g., an individual that initiates migration early relative to the rest of

[9] Query: how do birds adjust migration routes with climate change
Title: Genetics and Evolution of Bird Migration
URL: https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239
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[[Citing articles]](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#)[[Web of Science]](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#)[[Medline]](https://www.annualreviews.org/content/journals/10.1146/annurev-animal-021122-092239#)
## Literature Cited

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[Assistant]
Birds adjust their migration routes in response to climate change and habitat loss through a combination of genetic, physiological, and behavioral adaptations. Key findings from the research include:

1. **Genetic Adaptations**:
   - Migratory behavior is under genetic control, with some species showing rapid adaptation by altering migration schedules.
   - Genetic variation allows for phenotypic plasticity, enabling some birds to adjust migration timing and routes.
   - Some species, like the Richard’s pipit, have evolved new migration routes due to climate-induced changes in habitat suitability.

2. **Physiological Adaptations**:
   - Birds adjust migration timing and speed based on energy reserves and stopover site quality.
   - Changes in migration strategies include delaying departure to cope with drought or habitat degradation, and accelerating migration to compensate for lost time.
   - Birds may alter their migration routes to minimize energy expenditure, using stopover sites strategically to refuel.

3. **Behavioral Adaptations**:
   - Birds use environmental cues such as temperature and food availability to adjust migration timing.
   - Some species shift their migration destinations, with studies showing movements of up to half a degree of latitude northward in response to climate change.
   - Birds may modify their flight paths based on wind conditions and weather patterns to optimize energy use.

4. **Challenges and Limitations**:
   - Not all species can adapt quickly enough to keep pace with rapid climate change, leading to phenological mismatches and reduced breeding success.
   - Light pollution and habitat loss further complicate migration, affecting bird behavior and survival.
   - Some species maintain traditional routes despite environmental changes, which can lead to detours and increased energy costs.

5. **Ecological Impacts**:
   - Changes in migration patterns affect ecosystems by altering predator-prey relationships and seed dispersal.
   - Birds that no longer migrate to certain areas can disrupt local ecological functions, such as pollination and pest control.

6. **Research and Conservation**:
   - Studies using tracking and genetic analysis help identify key stopover sites and migration corridors for conservation.
   - Conservation efforts must consider the specific migration strategies of different species, including the importance of stopover sites and the timing of migration.

In summary, birds adjust their migration routes through a combination of genetic predispositions, physiological flexibility, and behavioral responses to environmental cues. However, the speed and extent of climate change pose significant challenges, and not all species are equally capable of adapting.