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At least 19 recordsLinked to original sources

Status of native freshwater mussels in Copper Creek, Virginia

Previous freshwater mussel surveys conducted in Copper Creek showed a decline in the fauna from 1980 to 1998. In 2004 and 2005, we sampled 47 sites acquiring relative abundance estimates (measured in catch-per-unit-effort) to assess the current status of the mussel fauna relative to previous surveys. We also obtained absolute density estimates for 4 select sites for comparison with future and past surveys. Of the 25 mussel species reported from this and previous surveys, 16 were represented by living specimens, 5 are extant but may soon be extirpated, and 8 are likely extirpated from the creek. Presence-absence analysis showed a significant decline in species per site since 1980. Absolute density estimates (at Copper Creek river km 3.1) decreased significantly from 4.07 mussels/m 2 in 1981 to 0.63 mussels/m 2 in 2005. The cause of this faunal decline is likely due to several factors, including, most notably, the loss of riparian buffers. Nearly half of the stream banks in Copper Creek have inadequate riparian vegetation to provide even minimal sediment control. Precipitous declines of the Clinch River fauna (a likely source population for several species) may be another significant factor influencing the faunal decline in Copper Creek. Despite these declines, populations of several species may be in a state of recovery. Based on 18 comparable sites, average catch-per-unit-effort in 2005 was 25.16 mussels/hr, significantly higher than the 1998 survey (12.92 mussels/hr).

Virginia

Influence of small impoundments on habitat and fish communities in headwater streams

We surveyed the habitat and fish assemblages of four impounded and three unimpounded neighboring headwater streams, separated longitudinally into multiple upstream and downstream reaches. Instream habitat characteristics were similar between reaches of unimpounded streams and reaches above impoundments, and differed significantly from reaches below impoundments that included deeper water and more stable flows. Species richness was similar above and below impoundments, and between impounded and unimpounded streams, but fish assemblage composition and structure differed. Stream reaches above impoundments supported higher percentages of centrarchids compared to upper reaches of unimpounded streams, which had more obligate stream cyprinids. Reaches below impoundments supported mainly centrarchid species whereas lower reaches of unimpounded streams supported a balanced mix of cyprinids and centrarchids. Percina maculata (Blackside Darter) occurred throughout the study area except in upper reaches of impounded streams, illustrating how stream fragmentation can lead to localized extirpations. Changes to the fish assemblages in reaches above impoundments were due to the loss of downstream connectivity, and changes to the fish assemblages below impoundments were due to alterations of instream habitat caused by the impoundments. Small impoundments can have important effects on fish faunas of small geographical areas, but also potentially large cumulative effects if distribution of impoundments is not administered strategically at the scale of the river basin. We caution that continual population increase, recent droughts, and projected changes in climate patterns are prompting a renewed interest in impoundment construction, and urge close regulatory oversight over such projects.

Southeastern Naturalist

Site characteristics and prey abundance at foraging sites used by Lesser Scaup ( Aythya affinis ) wintering in Florida

We examined site characteristics and prey abundances where wintering Aythya affinis (Lesser Scaup; hereafter scaup) foraged within three regions of the Indian River Lagoon system in central Florida. We observed that scaup concentrated in the Indian and Banana rivers; however, density of prey items did not differ between foraging sites and random sites. We also found that site characteristics were similar between foraging and random sites. Differences in site characteristics between random points across all three regions did not explain the distribution of Foraging scaup (no scaup foraged in the Mosquito Lagoon); however, prey densities were approximately 3 times lower in the Mosquito Lagoon region. Our study suggests that current habitat conditions within the northern Indian River Lagoon system meet the overwintering requirements of scaup; however, prey densities in the Mosquito Lagoon may have been too low to be profitable for foraging scaup during the period of our study.

Florida

Vegetation effects on fish distribution in impounded salt marshes

We compared the density and biomass of resident fish in vegetated and unvegetated flooded habitats of impounded salt marshes in the northern Indian River Lagoon (IRL) Estuary of east-central Florida. A 1 -m 2 throw trap was used to sample fish in randomly located, paired sample plots ( n = 198 pairs) over 5 seasons in 7 impoundments. We collected a total of 15 fish taxa, and 88% of the fishes we identified from the samples belonged to three species: Cyprinodon variegatus (Sheepshead Minnow), Gambusia holbrooki (Eastern Mosquitofish), and Poecilia latipinna (Sailfin Molly). Vegetated habitat usually had higher density and biomass of fish. Mean fish density (and 95% confidence interval) for vegetated and unvegetated sites were 8.2 (6.7–9.9) and 2.0 (1.6–2.4) individuals m -2 , respectively; mean biomass (and 95%) confidence interval) for vegetated and unvegetated sites were 3.0 (2.5–3.7) and 1.1 (0.9–1.4) g m -2 , respectively. We confirmed previous findings that impounded salt marshes of the northern IRL Estuary produce a high standing stock of resident fishes. Seasonal patterns of abundance were consistent with fish moving between vegetated and unvegetated habitat as water levels changed in the estuary. Differences in density, mean size, and species composition of resident fishes between vegetated and unvegetated habitats have important implications for movement of biomass and nutrients out of salt marsh by piscivores (e.g., wading birds and fishes) via a trophic relay.

Florida

Freshwater mussels (Unionidae) in the headwaters of Chipola River, Houston County, Alabama

Big and Cowarts creeks lie in extreme southeastern Alabama and form the headwaters of Chipola River. Qualitative and quantitative sampling for freshwater mussels in these reaches during 2006 and 2007 revealed an intact fauna, relative to historical reports. A cumulative total of 17 species, including federally protected Elliptio chipolaensis (Chipola Slabshell), Lampsilis subangulata (Shinyrayed Pocketbook), Medionidus penicillatus (Gulf Moccasinshell), and Pleurobema pyriforme (Oval Pigtoe), was encountered. A total of 3382 mussels (density 5.84 per m 2 ) was estimated for one 65-m reach of Big Creek and 9627 mussels (density 8.09 per m 2 ) were estimated to occur in one 170-m reach of Cowarts Creek. Tributaries had depauperate faunas, apparently due to substrate instability.

Southeastern Naturalist

Mussel remains from prehistoric salt works, clarke county, Alabama

Archaeological research at salt springs in Clarke County, AL (Tombigbee River drainage), documented bivalve mollusk exploitation by late prehistoric American Indians. A total of 582 valves representing 19 species of freshwater mussels (Unionidae) and an estuarine clam (Mactridae) from the Lower Salt Works Site (ca. A.D. 900-1550) and 41 valve fragments representing 6 mussel species from the Stimpson Site (ca. A.D. 1200-1550) were documented. The Lower Salt Works fauna was dominated numerically by Fusconaia ebena and Quadrula asperata, the dominant species reported during recent local surveys. The mussel species represented are known from medium to large streams in sand and gravel habitats and include four federally protected species and other species of conservation concern in Alabama. Results offer comparative data for other archaeological and ecological studies in the region.

Southeastern Naturalist

First record of carpiodes velifer (Highfin Carpsucker) in the Apalachicola River, Florida

We document the discovery of Highfin Carpsucker in the Apalachicola River, FL. Three specimens were captured between river kilometer 170-171 on the Apalachicola River in the vicinity of Jim Woodruff Lock and Dam during spring 2007, The specimens were captured within a reach 0.5-1.0 km downstream from the dam and just upstream from a major spawning area for several other catostomids. This is the first record of the species east of the Choctawhatchee River, FL-AL, and is a range extension of 185 km eastward into the Florida Panhandle region of the Northern Gulf of Mexico Coast.

Southeastern Naturalist

Systematic status of wild Canis in North-central Texas

Skulls of wild Canis collected 2003–2004 in north-central Texas are morphometrically similar to a series taken there and in nearby areas in 1964–1971, which was considered to represent a population of Coyotes ( C. latrans ) modified through introgression from Red Wolves ( C. rufus ). A few of the new specimens closely resemble small examples of Red Wolves. Such affinity is supported by authoritative examination of living and videotaped animals. The persistence of influence of Red Wolves, long after presumed extirpation through hybridization and human persecution, may be relevant to wolf conservation.

Texas

The persistence of endangered Florida Salt Marsh Voles in salt marshes of the central Florida Gulf Coast

Two endangered Microtus pennsylvanicus dukecampbelli (Florida Salt Marsh Vole) were captured at a new location, in February of 2009, at Lower Suwannee National Wildlife Refuge. Since the species discovery in 1979, only 43 Florida Salt Marsh Voles (hereafter FSM Vole) have been captured. Outside of the type locality, this is only the second documented location for the FSM Vole. Given the difficulty in trapping this species and the lack of information about its life history, its discovery in a new location lends itself to the possibility that it is more widespread in the Central Florida Gulf Coast than previously thought. Although much of the salt marsh in the area is in public ownership, a good deal of it has already been altered by logging or development and is threatened by global climate change. More research is needed to adequately protect and manage the habitat for the FSM Vole. A study of FSM Vole coastal salt marsh habitat could also serve as a valuable monitoring tool for subtle changes in salt marsh habitats as global climate change progresses.

Southeastern Naturalist

Distribution and conservation standing of West Virginia crayfishes

The diversity of crayfishes in West Virginia represents a transition between the species-rich southern Appalachian faunas and the depauperate crayfish diversity in the northeastern United States. Currently, 22 described species occur in the state, of which 6 are given S1 status, and 3 are introduced species. One species, Orconectes limosus (Spinycheek Crayfish) is considered extirpated within the past decade. Imperiled species include Cambarus veteranus (Big Sandy Crayfish), Cambarus elkensis (Elk River Crayfish), Cambarus longulus (Atlantic Slope Crayfish), and Cambarus nerterius (Greenbrier Cave Crayfish). Three species— O. virilis (Virile Crayfish), Orconectes rusticus (Rusty Crayfish), and Procambarus zonangulus (Southern White River Crawfish)—have introduced populations within the state. Procambarus acutus (White River Crawfish) occurs in bottomland forest along the Ohio River floodplain, and is considered native. Several undescribed taxa have been identified and currently are being described. A statewide survey was initiated in 2007 to document the current distribution and conservation status of crayfishes in West Virginia.

West Virginia

Common Grackle breeding on bottomland forest restoration sites

Two of 36 forest restoration sites in the Mississippi Alluvial Valley surveyed from 2000-2002 harbored Quiscalus quiscula (Common Grackle). Occupied sites were in less-forested landscapes and had sparser understory vegetation due to flooding. Probability of daily nest survival (0.9077) of 169 Common Grackle nests was influenced by nest-placement, temporal, and landscape effects. Age of nest markedly affected nest survival, which increased from <0.89 during egg laying (age < 6 days) to >0.92 when nestlings were present (age > 18 days). Extrapolating daily nest survival to a 31 -day nest period resulted in 5% nest success, far less then previously estimated for this species in more northern latitudes and likely less than required to sustain populations on these sites.

Southeastern Naturalist

Life-history notes on Cambarus hubbsi creaser (Hubbs crayfish) from the South Fork Spring River, Arkansas

Many crayfish species native to the southeastern United States are imperiled due to small range sizes and anthropogenic impacts such as habitat loss and introduction of non-native species. Furthermore, effective management of crayfish is limited by the scarcity of life-history and ecological data for many of these species. We report results of the first life-history study of the crayfish Cambarus hubbsi (Hubbs Crayfish). We collected 466 Hubbs Crayfish from the South Fork Spring River, AR throughout 2006 and recorded carapace lengths, wet weights, indicators of reproductive activity, and number of eggs on ovigerous females. Using length-frequency distributions, we identified four Hubbs Crayfish age classes and evaluated growth rates by plotting size by season (winter, spring, summer, autumn). Male Hubbs Crayfish were more common than females in all seasons except autumn, and males weighed more at equivalent lengths than females. Reproductive activity in Hubbs Crayfish peaked in late winter and spring, and ovigerous females were collected in March, April, and June. Ovigerous females were age II or III and carried few eggs relative to co-occurring crayfish of the genus Orconectes. Compared to these Orconectes species, Hubbs Crayfish is comparatively slow growing, long lived, with low reproductive potential, and as a result may be categorized as a K life-history strategist. Based on this species' life-history strategy and previously documented habitat specificity and taxonomic distinctiveness, Hubbs Crayfish may require monitoring and management attention normally reserved for species with smaller ranges.

Southeastern Naturalist

Larval fish dynamics in spring pools in middle Tennessee

We used lighted larval traps to assess reproduction by fishes inhabiting nine spring pools in the Barrens Plateau region of middle Tennessee between May and September 2004. The traps ( n = 162 deployments) captured the larval or juvenile forms of Etheostoma crossopterum (Fringed Darter) ( n = 188), Gambusia affinis (Western Mosquitofish) ( n = 139), Hemitremia flammea (Flame Chub) ( n = 55), the imperiled Fundulus julisia (Barrens Topminnow) ( n = 10), and Forbesichthys agassizii (Spring Cavefish) ( n = 1). The larval forms of four other species (Families Centrarchidae, Cyprinidae, and Cottidae) were not collected, despite the presence of adults. Larval Barrens Topminnow hatched over a protracted period (early June through late September); in contrast, hatching intervals were much shorter for Fringed Darter (mid-May through early June). Flame Chub hatching began before our first samples in early May and concluded by late-May. Juvenile Western Mosquitofish were collected between early June and late August. Our sampling revealed that at least two species (Flame Chub and Fringed Darter) were able to reproduce and recruit in habitats harboring the invasive Western Mosquitofish, while Barrens Topminnow could not.

Southeastern Naturalist

Cerulean Warbler occurrence and habitat use in Oklahoma

Dendroica cerulea (Cerulean Warbler) is a migrant songbird that has declined rangewide in recent decades. We surveyed 150 sites in 2006&ndash;2007 to determine if this species still occupied its former breeding range in Oklahoma. We located Cerulean Warblers at 5 sites and confirmed breeding on north slopes of two heavily forested ridges in the Ouachita Mountains. We did not encounter Cerulean Warblers in any bottomland hardwoods, despite the former widespread distribution and abundance of the species in such habitats. While habitat loss and degradation may limit occurrence of Cerulean Warbler in some areas, the pattern of decline for this species at the edge of its range in Oklahoma is also consistent with abandonment of peripheral range as the range-wide population declines.

Oklahoma

Population densities of painted buntings in the southeastern United States

The eastern population trend of Passerina ciris (Painted Bunting) declined 3.5% annually during the first 30 yrs of the Breeding Bird Survey (BBS, 1966&ndash;1996). Recently, the US Fish and Wildlife Service listed Painted Buntings as a focal species. Surveys for this focal species for the next 10 yrs (BBS, 1997&ndash;2007), however, are too low (<1 bird per 50 stops) for determining trend estimates. Also, to monitor densities adequately, surveys should account for incomplete detections. I surveyed singing Painted Buntings from 13 May to 26 June 2003 at 582 point counts (50 randomly selected transects) within blocks (64 × 64 km) in coastal and river areas from Florida to North Carolina. I compared densities of Painted Buntings for major habitats. Painted Buntings were detected at 33.5% of points surveyed for 5 min. Densities varied from 9 singing males per km 2 in young pine plantations to 42 per km 2 in maritime shrub. Effective detection radii for habitats varied from 64 to 90 m and were slightly higher in developed than in undeveloped habitats. Distance sampling is recommended to determine densities of Painted Buntings; however, large sample sizes (70&ndash;100 detections/habitat type) are required to monitor Painted Bunting densities in most habitats in the Atlantic coastal region of the southeastern United States. Special attention should be given to maritime shrub habitats, which may be important to maintaining the Painted Bunting population in the southeastern US.

Florida, Georgia, North Carolina, South Carolina

Rapid change in the defense of flightless young by a mourning dove parent

We report that an adult-sized Zenaida macroura (Mourning Dove), presumably a parent, rapidly decreased risk taken in defense of a juvenile as the likelihood of predation to the juvenile increased. We attribute this decrease in risk taken to (1) the parent's perception that the risk of predation had increased to the extent that a continuation of defensive behaviors would not prevent the death of the juvenile, and (2) its attempt to minimize its own risk of death. It may be that there is a threshold beyond which Mourning Dove parents will forgo the risk of additional defense of offspring in favor of making another reproductive attempt.

Southeastern Naturalist

Status and distribution of breeding secretive marshbirds in the Delta of Arkansas

We surveyed the Lower Mississippi Alluvial Valley of Arkansas ("the Delta") during the breeding seasons of 2005 and 2006 using the national marshbird monitoring protocol for secretive marshbirds. We detected and documented breeding by Podilymbus podiceps (Pied-billed Grebe), Ixobrychus exilis (Least Bittern), Rallus elegans (King Rail), and Gallinula chloropus (Common Moorhen). We detected but did not document breeding by Botaurus lentiginosus (American Bittern), Porphyrula martinica (Purple Gallinule), and Fulica americana (American Coot), all of which have been documented to breed in the Delta. Our estimated occupancy rates for breeding marshbirds in the study area ranged from a low of 6% for the King Rail in 2006 to a high of 27% for the Least Bittern in 2005. The range of these occupancy rates are low and reflect the rarity of secretive marshbirds in the Delta. Secretive marshbird occupancy rates were higher in the southern third of the Delta, probably because wetlands were more abundant or of higher quality there.

Southeastern Naturalist

Prevalence of a potentially lethal parasite of wading birds in natural and agricultural wetlands in south Louisiana

Gambusia affinis (Western Mosquitofish) were sampled from 18 sites representing marsh, forested wetlands, and agricultural wetlands in south Louisiana to determine distribution and infection parameters of Eustrongylides ignotus , a potentially lethal nematode parasite of wading birds, ( n = 400 per site). Overall, prevalence of infection was 0.3%, with significantly higher prevalence in agricultural wetlands than in marshes or swamps. Our findings are similar to work in Florida suggesting parasite prevalence is higher in disturbed wetlands, and suggest that birds foraging in crayfish ponds and rice fields may be at increased risk of exposure.

Louisiana