Datasets:
patrickbdevaney
/
mia9

Dataset card Data Studio Files
xet
 Community
1
text
stringlengths
0
6.44k
toxicant exposure. Body burdens could be correlated
with various health-assessment indices that describe
the status of population health. Through NOAA and
its collaborators, a program is gradually evolving that
characterizes toxicant body burdens and blood profiles
of dolphin populations in various estuaries of the
southeastern United States. Information from the resident Biscayne Bay dolphin population could therefore
be used to compare toxicant exposures in Biscayne
Bay to other estuaries. Such an effort would be facilitated by the ongoing NOAA project to identify and
catalogue resident dolphins of the bay to distinguish
them from members of coastal migrant populations
and to determine local movements.
Manatees
The relationship of manatees to stressors is depicted
in diamonds 3 and 4 of Figure 2. Manatees are directly
EXHIBIT 7
866 WETLANDS, Volume 25, No. 4, 2005
affected by floodgate closures, a documented cause of
mortality. They may also be affected by the way that
canals and levees have concentrated the availability of
fresh water at a few sites, almost all near floodgates.
Relationship of Manatee Distribution to Timing, Location, and Volume of Freshwater Inflow. Changes
in timing, location, and volume of freshwater inflow
could affect manatee distribution within the bay and
their use of canal habitat. For example, restoration of
more natural and stable freshwater creeks and springs
may enhance manatee habitat in areas more remote
from human threats. However, complete elimination of
existing canals (or access to them) or discharge structures may disrupt behavior of individual manatees that
traditionally utilize such sites.
Relationship of Manatee Mortality to Water-Control
Structure Operations. Water control floodgates are
the leading cause of determinable manatee mortalities
in Biscayne Bay (Mayo and Markley 1995, FWC
1999, USFWS 2001). Miami-Dade County leads the
state in floodgate and other human-related causes of
manatee mortality. Manatees are attracted to canals as
a source of fresh water and cold-weather refuge. Over
the last two decades, water-control-structure operations have been modified, and some gates have been
retrofitted with pressure-sensitive devices that are supposed to prevent the gates from closing on an object.
Although this has resulted in some improvement, mortalities have continued. Modification of gates or their
operation may affect manatee mortality. For example,
if water normally discharged through a coastal watercontrol gate were diverted into a series of creeks, as
planned in the Biscayne Bay Coastal Wetlands Project
of CERP, then the frequency that the gate opens and
closes would be reduced, thereby reducing the risk to
manatees. The number of manatees in Biscayne Bay
increases during cold weather, increasing vulnerability
to human related impacts (e.g., control structures and
boats) during that time of year, so gate operations are
particularly important then.
Wading Birds
Relationship of Wading Bird Nesting Activity, Nesting
Success and Foraging Activity to Water-Management
Structures and Their Management. The relationship
of wading birds to stressors is primarily through effects expressed in diamond 3 of Figure 2. Lorenz
(2001a,b) showed that nesting success of roseate
spoonbills in one colony (Tern Key) was detrimentally
affected by changes in water stages caused by watermanagement structures and operations near Florida
Bay. Feeding opportunities for roseate spoonbills and
other wading birds also have been diminished by the
reduction in freshwater flow to Biscayne Bay wetlands
resulting from road construction and diversion of water into canals. Modification of the structure and operation of the water-management system in relation to
Biscayne Bay wetlands could affect nesting success at
the Tern Key site in eastern Florida Bay. Improvements in water management might also affect activity
and nesting success of colonies of wading birds that
nest on islands within Biscayne Bay.
RESEARCH QUESTIONS
Science issues were identified based on the hypotheses encapsulated in the conceptual ecological model.
Those considered most important to address before
restoration construction plans are finalized were consolidated into a set of 14 research questions. The selection of the most important science issues was by
informal concensus in the workshops organized to develop the model and was based primarily on the degree
to which the topic was considered to be fundamental
to the success of Biscayne Bay restoration and relative
uncertainty. The following 14 research questions,
roughly priorized by the authors, were identified.
1. What is the quantitative relationship between upstream water management, rainfall, and flow into Biscayne Bay? 2. How is estuarine habitat affected by
quantity, timing, and distribution of freshwater inflow?
3. What salinity gradient from interior coastal wetlands
through the nearshore zone would optimize diversity
and abundance of oligotrophic and mesohaline fish
species in the bay and its coastal wetlands? 4. What is
the quantitative relationship between nutrient and contaminant loads and spatial and temporal patterns of
water-quality and sediment-quality? 5. Will use of reclaimed wastewater as a significant component of
freshwater inflow have ecological, water quality, or
sediment quality effects? 6. How is juvenile pink
shrimp abundance affected by changes in quantity,
timing, and distribution of freshwater inflow, and is
there a direct quantitative relationship between juvenile pink shrimp abundance and fishing success? Is the
catch per unit of effort in these fisheries affected by
freshwater inflow? 7. How might proposed changes in
water management affect seagrass distribution, density, species composition, and dominance in the western
nearshore area? 8. What are the effects of freshwater
inflow change and sea-level rise on the white zone? 9.
What is the functional relationship of toxicant concentrations and fish exposure to the types of abnormalities
prevalent in Biscayne Bay fish? 10. What is the actual
exposure to toxicants of the bottlenose dolphins in Biscayne Bay? 11. Will changes in freshwater volume and
delivery affect manatee distribution, particularly in
south Biscayne Bay? 12. What effects will changes in
EXHIBIT 7