Datasets:
patrickbdevaney
/
mia9

Dataset card Data Studio Files
xet
 Community
1
text
stringlengths
0
6.44k
Spotted sea trout (Cynoscion nebulosus) and mojarras
(Eucinostomus spp.) are important fish species in Biscayne
Bay. Serafy et al. (1997) found that populations of these two
species in Biscayne Bay prefer salinities less than 20 ppt. They
also found a significant decline in the abundance of these two
species from 20 to 30 ppt. A re-examination of these data,
with the addition of silver perch (Bairdiella chrysoura), was
conducted to focus on evaluating the relationship between
salinity and juvenile abundance (Fig. 4). A clear pattern of selection of salinities less than 20 ppt was observed in the data,
with significant declines in abundance from 20 to 30 ppt. The
pattern of declining fish density with increasing salinity was
also observed by Campos (1985) in another study conducted
in Biscayne Bay.
Pink shrimp (Farfantepenaeus duorarum) are a key species
in the marine food chain and they are the most economically
important fishery in Biscayne Bay (Bielsa et al. 1983; Berkeley
and Campos 1984; Markley and Milano 1985; Browder et
al. 1999; Serafy et al. 2001). Estuaries, and the seagrass communities found there, are important nursery habitats for pink
shrimp, offering the most favorable food and shelter conditions for juvenile and post larval pink shrimp (Bielsa et al.
1983; Ault et al. 1999). Young shrimp find their way into the
estuary by detecting lower salinity and a high amount of organic material (Lindall 1971; Odum and Heald 1975; Ault et al.
1999). These shrimp spend 2-6 months in estuarine areas before entering offshore water (Costello and Allen 1966; Bielsa
et al. 1983; Ault et al. 1999). Post-larval pink shrimp are most
often found in the nearshore seagrass on the western side of
the central and southern portions of Biscayne Bay (Ault et
al. 1999). Since this species is critically important to the bay
and the regional fishery, estuarine conditions and SAV habitat must be preserved. This can only be accomplished by the
stabilization and persistence of mesohaline conditions.
Table 1. Fish and wildlife indicators in Biscayne Bay.
Organism Zone Importance Source
American crocodile (Crocodylus acutus) Mangroves
Spotted seatrout (Cynoscion nebulosus) Western Bay Zone
Mojarras (Eucinostomus spp.) Western Bay Zone
Silver perch (Bairdiella chrysoura) Western Bay Zone
Pink shrimp (Farfantepenaeus duorarum) Western Bay Zone
Eastern oyster (Crassostrea virginica) Mangroves
Endangered Species
Commercial value, Recreational
fishing
Forage base species
Forage base species
Keystone species, commercial value
Commercial value
Mazzotti and Cherkiss, 1998; Kushlan and
Mazzotti 1989. Kushlan 1988; Mazzotti
1983
Pattillo, et al 1997; Bortone, 2003.
Serafy, et al., 1997
Serafy, et al., 1997
Bielsa et al., 1983; Serafy et al., 2001;
Browder et al., 1999; Gunter et al., 1964
Meeder et al., 2001, Wells, 1961
10 South Florida Natural Resources Center Technical Series (2006.1)
m ojarras
Figure 4. Abundance of key indicator fishes relative to salinity
(from Serafy et al. 1997).
Desired Conditions
Coastal Mangrove Zone. In the CMZ, these low salinity
values will sustain a fully-functional tidal wetland transition
zone, and estuarine creeks that provide freshwater to the bay
will result in stable estuarine conditions for nearshore habitats. Coastal creeks, currently intercepted by the L31E levee,
should have a normal seasonal hydrograph, with flows in the
wet season that are dominated by local rainfall, and declining
flows in the dry season, dominated by base flows from inland
drainage. The level of freshwater discharged into Biscayne
National Park should support SAV dominated by wigeon
grass and Chara spp. Emergent vegetation should consist of
cord grass (Spartina spp.), salt grass (Distichlis spicata), and
black rush (Juncus roemerianus). The existing mangrove forest should remain similar to what it is now, but should consist
of a more spatially distinct buttonwood, black mangrove, and
white mangrove transition zone, with red mangroves at the
edges of creeks and at the bay’s shoreline.
The faunal composition in the mangrove zone should be
similar to that described in historical documentation of predrainage conditions, and where it is not detailed, composition
should be similar to fauna characteristic of less impacted estuarine mangrove forests in south Florida. The desired species are those common to coastal streams and inland brackish
marsh flats, such as the sailfin molly (Poecilia latipinna), goldspotted killifish (Floridichthys carpio), sheepshead minnow
(Cyprinodon variegatus), and eastern mosquitofish (Gambusia holbrooki) (Lorenz 1999; Serafy et al. 2003).
In the subtidal area of the CMZ, which is dominated by
mangrove prop roots, permanent, healthy oyster communities should be common on the prop roots and as oyster reefs
where the creeks enter the bay. Although oysters were once
common in the bay and are characteristic of similar habitats in
south Florida, they are only found in very low numbers today.
Establishment of more normal volumes, timing, and distribution of water deliveries will foster the restoration of oyster
colonies and the estuarine biota associated with them.
Western Bay Zone. Estuarine conditions in the WBZ will
maximize SAV coverage and diversity, a key component of
critical nursery and juvenile fishery habitats. Under appropriate salinity and water quality conditions, it is expected that the
WBZ will sustain excellent SAV growth where sediment and
water depth are appropriate. These salinities should also create a more diverse seagrass community, dominated by species
that do well under estuarine conditions. Wigeon grass will be
the dominant species at the mangrove/nearshore ecotone and
shoal grass will be co-dominant with turtle grass throughout
the WBZ. Maintaining estuarine salinity would sustain larval
and juvenile red drum and provide good habitat conditions
for sustaining a forage-base for red drum, including oyster,
shrimp, and forage fish populations.
In general, water deliveries to Biscayne National Park
should not result in damage to natural resources or extreme
salinity conditions that adversely affect fishery and wildlife
resources. The preferred salinity ranges for the indicator species help determine how much of the current water deliveries