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At least 73 records · Page 4Linked to original sources

USGS2018

Exotic invasive Pomacea maculata (Giant Apple Snail) will depredate eggs of frog and toad species of the Southeastern US

Pomacea maculata (Perry) (Giant Apple Snail) is a freshwater snail native to South America ( Hayes et al. 2015 ) that is an invasive species in the freshwater wetlands and waterways of the northern Gulf of Mexico, peninsular Florida ( Benson 2017 , Burks 2017 ) and globally ( Hayes et al. 2015 ). Karraker and Dudgeon ( 2014 ) found that Pomacea canaliculata (Lamarck) (Channeled Apple Snail) opportunistically ate frog eggs. The Giant Apple Snail is a sister species to the Channeled Apple Snail and shares similar life-history attributes ( Hayes et al. 2015 ). However, the literature indicates that Giant Apple Snail is presumed to be an herbivore (e.g., Burke et al. 2017 , Burlakova et al. 2009 ). Will Giant Apple Snail eat amphibian eggs? If they do, they could have a negative impact on anuran populations throughout their introduced range. In this study, we presented Giant Apple Snails with frog and toad eggs to determine if they would eat them.

Southeastern Naturalist↗

USGS2018

Intensive sampling reveals underreported use of great-river tributaries by large-river fishes in Missouri

Large tributaries may help sustain large-river fish populations by mitigating fish-habitat losses within the highly modified great rivers of the Mississippi River basin. These tributaries are likely most beneficial for fish species specializing on non-degraded large-river habitat for some portion of their life histories. Few great-river tributaries, however, have been surveyed using methods that comprehensively target all fish species, resulting in uncertainty or bias in the reported composition of many tributary fish assemblages. We report important distributional records, including 23 new accounts, for 12 large-river specialist fishes in Missouri —Alosa alabamae (Alabama Shad), Cycleptus elongatus (Blue Sucker), Pimephales vigilax (Bullhead Minnow), Notropis wickliffi (Channel Shiner), Polyodon spathula (Paddlefish), Hybognathus placitus (Plains Minnow), N. blennius (River Shiner), Macrhybopsis hyostoma (Shoal Chub), Scaphirhynchus platorynchus (Shovelnose Sturgeon), M. storeriana (Silver Chub), Ichthyomyzon unicuspis (Silver Lamprey), and Alosa chrysochloris (Skipjack Herring)—following 38 comprehensive fish surveys in tributaries of the Missouri and Mississippi rivers. New accounts collectively demonstrate tributaries support more large-river specialists than historically documented and thus may be currently undervalued sources of habitat for large-river fishes.

Missouri↗

USGS2018

Photographs of wading bird depredation events to monitor invasion extent of Asian Swamp Eel (Monopterus albus)

Several anecdotes exist of wading birds depredating invasive Monopterus albus (Asian Swamp Eel) in waterways of the conterminous US. We present photographic evidence of 4 different wading bird species depredating adult Asian Swamp Eels in Georgia and Florida herein. Photographs taken by wildlife enthusiasts could provide a means for early detection of the Asian Swamp Eel and other aquatic species that are challenging to detect in waterways.

Florida, Georgia↗

USGS2019

Genetic Characterization of Non-Native African Jewelfish, Hemichromis letourneuxi Sauvage 1880, in Florida

The African Jewelfish, Hemichromis letourneuxi , is an invasive, predatory cichlid fish introduced at least once to Florida. Its native range is in northern Africa. First encountered in Miami in the 1960s, it has since been found west and north within the State of Florida. It thrives in a wide range of aquatic habitats, including shallow, vegetated or rocky areas of canals, tidal creeks, rivers, and marshes. We generated mitochondrial DNA sequences from 6 Florida localities, and 1 Mexico population. The resulting tree describes recent historical relationships among populations. Nearly all Florida populations of African Jewelfish are intermixed, supporting a single invasion, with one possible exception: samples from the Tampa Bay locality are distinct and may represent a separate introduction. Samples obtained from the Mexico locality, previously identified as Hemichromis guttatus (Spotted Jewelfish), appear to be genetically identical to, and indistinguishable from the H. letourneuxi sampled in Florida localities.

Florida↗

USGS2020

Identifying life history traits that promote occurrence for four minnow (Leuciscidae) species in intermittent Gulf Coastal Plain streams

- Life history traits of stream fishes partly reflect adaptations to disturbance regimes, which in turn shape assemblage composition via environmental filters. In this study, we focused on life history traits of four morphologically similar leuciscid species in coastal plain streams of southwestern GA that are shifting from historically perennial to intermittent flow. We evaluated differences in reproductive timing, sex ratio, body size at maturity, reproductive investment, and diet, traits hypothesized to influence species persistence in intermittent streams. We first ordinated published species occurrence data for samples of fish communities in perennial and intermittent streams in the study region, and identified four focal taxa as differing in their associations with intermittency. We then periodically sampled individuals of the focal taxa in 14 streams over a year (May 2016-April 2017). We found that for Pteronotropis harperi (Redeye Chub), a species strongly associated with intermittent streams, reproductive timing did not overlap with typical seasonal stream drying. Redeye chub also had the significantly smallest minimum length at maturation and the greatest reproductive investment. Fishes associated with perennial streams (Pteronotropis grandipinnis (Apalachee Shiner) and Notropis petersoni (Coastal Shiner)), or not associated with either stream type (Notropis texanus (Weed Shiner)), had at least a portion of their reproductive timing overlapping with times when streams were likely to dry, and had similar and significantly lower reproductive investment than Redeye Chub. Redeye Chub displayed no shift in diet when streams ceased flowing, while Apalachee Shiner showed decreases in terrestrial prey. Our results suggest that the size at maturity, reproductive timing, and reproductive investment may promote persistence by the Redeye Chub given projections of more frequent and intense periods of stream intermittency.

Gulf Coast↗

USGS2020

The influence of groundwater on the population size and total length of warmwater stream fishes

Groundwater influences stream environments in numerous ways including structuring biotic assemblages. However, associations between groundwater influence and warmwater fish assemblages are under-studied. We examined relationships between groundwater contribution, population size, and total length (TL) for 5 warmwater fishes at 32 stream reaches in the Ozark Highlands ecoregion. When we controlled for distance from an impoundment, population size and TL were significantly related to groundwater influence for all 5 species. Sunfishes were significantly less abundant in reaches with high levels of groundwater contribution (HGC reaches), whereas Ambloplites rupestris (Rock Bass) and Nocomis asper (Redspot Chub) TLs were significantly greater at HGC reaches. Reach-scale groundwater contribution explained nearly 4 times more unexplained variation among fish densities than did TL. Our study provides insight into the structuring role of groundwater on warmwater fish populations.

Missouri, Oklahoma↗

USGS2020

Evidence for an established population of tegu lizards Salvator merianae in southeastern Georgia, USA

Documenting emergence of invasive species in new areas is vital to understanding spatiotemporal patterns of invasions, propagule pressure, and the risk of establishment. Salvator merianae (Argentine Giant Tegu) has established multiple unconnected populations in southern and Central Florida, and additional sightings have been reported elsewhere in the state. In 2018, land managers in Georgia received >20 reports of this species in the wild. To evaluate the probability of establishment, we assembled verified records of the non-native Argentine Giant Tegu in Georgia over the past nine years. We report on 47 tegu observations throughout Georgia, with a concentration of sightings (n = 38) in Toombs and Tattnall counties. In 2019, we used modified Havahart traps and captured adult male and female tegus at one of our three locations during 3085 corrected trap nights. While we did not find evidence of a well-established population (i.e., varied size structure of tegus captured) with our limited trapping effort, we suspect tegus are breeding in Toombs and Tattnall counties due to the concentration of captures and reports of adult males and females, the consistent reports of adults across years, the confirmed presence of tegus in 2018, 2019 and 2020, and the reproductive capacity (i.e., turgid testes and secondary follicles) of tegus captured. Ongoing tegu introductions from captivity are likely to maintain high propagule pressure in the southeastern United States. Effective early detection, funded rapid response networks, and public outreach to solicit reports of tegu sightings are critical to prevent establishment and associated ecological impacts of this invasive species elsewhere in the southeastern US.

Southeastern Naturalist↗

USGS2020

Effect of stream permanence on predation risk of lotic crayfish by riparian predators

Given the importance of crayfish in stream ecosystems, gaining insight into the role of stream permanence in maintaining predator–prey interactions is critical. Our objectives were to determine the influence of stream permanence and season on crayfish predation and assess the role of stream permanence and crayfish density on the presence of predators, while accounting for imperfect detection. We conducted surveys of crayfish density, mammalian scat, and environmental variables within 10 intermittent and 10 permanent streams in the Ozark Highlands. We used occupancy modeling to assess the relationship between predator presence, crayfish density, and environmental variables. Stream permanence did not play a role in determining relative frequency of occurrence or percent volume of crayfish prey in mammalian diets. However, percent volume and relative frequency of crayfish prey found in scats differed by season, with both highest in spring and summer. The relative frequency and percent volume of fish prey showed a significant interaction of season by stream permanence, which may be the first instance of this observation. Procyon lotor (Raccoon) had the highest detection probability ( p = 0.39), whereas Neovison vison (American Mink; p = 0.15) and Lontra canadensis (River Otter; p = 0.03) had low detection probabilities. Further study into predator–prey interactions in the context of hydrology, particularly when related to imperiled groups like freshwater crayfishes, is needed since climate change is expected to alter hydrologic patterns.

Arkansas, Missouri↗

USGS2021

Effects of surveying for the federally endangered Spruce-fir Moss Spider (Microhexura montivaga Crosby & Bishop) on its bryophyte habitat

Microhexura montivaga (Spruce-fir Moss Spider) is a federally endangered arachnid endemic to high-elevation montane conifer forests of the southern Appalachian Mountains. The spider is cryptic and difficult to monitor because this species lives in the interface between the bryophyte mat and the rock surface. Since temporary removal of the bryophyte mat is necessary to monitor the spider, surveyors may negatively impact the spider's habitat during monitoring. To help inform survey protocol for this endangered species, we studied reattachment rates of bryophyte mats to rock surfaces after their removal. In 2017, we surveyed sixty 10 cm × 10 cm plots, assigning a plot to either control or treatment (i.e., application of water post-reattachment). We monitored plots for 1 year post-survey to determine reattachment rates. The majority of plots (70%) reestablished after 1 year, whereas 15% did not reattach or showed substantial prolonged (e.g., ∼1 year) desiccation and 15% completely fell off or had 100% prolonged desiccation and were chlorotic. We found that mat depth and overstory canopy cover had no effect on mat reestablishment, although bryophyte type did. We found no difference between treatment and control plots, suggesting that no treatment is needed for mats to reestablish under the conditions described. Rock slope significantly influenced reestablishment rates, highlighting that surveying bryophyte mats on slopes >80% may diminish or destroy habitat. Further research is needed to determine long-term monitoring effects on the spider and its habitat, especially in relation to disturbance regimes and ecological restoration of Picea rubens (Red Spruce).

Southeastern Naturalist↗

USGS2021

Population density and stream-habitat relations of the Yellowcheek Darter (Nothonotus moorei) among the headwaters of the Little Red River in Arkansas

Nothonotus moorei (Yellowcheek Darter [YCD]) is an endangered species endemic to the headwaters of the Little Red River in north-central Arkansas. Population decline, habitat loss and fragmentation, and threats from land use and seasonal drought necessitate monitoring of population density and distribution to determine ecological and habitat associations. We evaluated YCD density and associated stream-habitat variables from 9 sites in the South Fork, Archey Fork, Middle Fork, and Beech Fork of the Little Red River from March to April 2018. Yellowcheek Darters were present at all 9 sites and 19 of 23 riffles sampled. Densities were generally comparable or higher than reported in previous studies, and we collected YCD at some sites at which they were considered previously extirpated, suggesting a rather stable population and evidence of recolonization of some sites since they were last surveyed. Yellowcheek Darter density was significantly negatively related to substrate embeddedness, and the consistent relation to embeddedness in this study and other studies suggest that this species is vulnerable to sedimentation.

Arkansas↗

USGS2021

Native mammalian predators can depredate adult Burmese Pythons in Florida

Invasive predators are of conservation concern because they contribute to species declines and extinctions worldwide. Interactions of native fauna and invasive predators can be complex, but understanding these relationships can guide management and restoration. Observations of these interactions are especially important for invaders with low detectability like Python bivittatus (Burmese Python) where data are sparse. Here, we provide the first detailed documentation of mammalian attacks on Burmese Pythons in Florida: 1 Lynx rufus (Bobcat) predation of an adult male python and 1 Ursus americanus floridanus (Florida Black Bear) non-lethal attack on an adult female python.

Florida↗

USGS2021

Predicted spatial distribution of the Eastern Spotted Skunk (Spilogale putorius) in Virginia using detection and non-detection records

The geographic distribution of a species is a fundamental component in understanding its ecology and is necessary for forming effective conservation plans. For rare and elusive species of conservation concern, accurate maps of predicted occurrence are particularly problematic and often highly subjective. Spilogale putorius (Eastern Spotted Skunk) populations have experienced large declines since the 1940s. Their elusive behavior and perceived rarity result in low detection probability when using conventional methods for sampling small mammals. Low detection probability often causes uncertainty as to where Eastern Spotted Skunks could be a management concern. We modeled the distribution of predicted occurrence of Eastern Spotted Skunks using verifiable occurrence and non-detection records obtained throughout Virginia from 2010 to 2020. Occurrence data consisted of trapping records reported to the Virginia Department of Wildlife Resources, incidental photo-verified reports of sightings and road-killed animals, and remote-camera detections. Non-detections were presumed at baited remote-camera locations following intense survey efforts. We fit predicted occurrence models using generalized linear modeling in an information-theoretic framework using the package ‘stats’ in Program R. Our results incidated a greater probability of presence from the Blue Ridge westward, increasing with slope steepness along northeastern- to southeastern-facing slopes and decreasing with slope steepness along southeastern- to southwestern-facing slopes. Emergent rock outcrops prominent along northeastern slopes offer ample protective rocky cover, whereas mixed Quercus spp. (oak), Kalmia latifolia (Mountain Laurel), and Rhododendron maximum (Rosebay Rhododendron) forest communities along southern-facing slopes provide suitable areas of cover, both of which are critical for spotted skunk survival and reproductive success. Our analysis provides insight into the relationships between landscape features and Eastern Spotted Skunk distributions across Virginia. Understanding these relationships is critical for the effective management and conservation of this vulnerable species.

Virginia↗

USGS2021

Demography of the Appalachian Spotted Skunk (Spilogale putorius putorius)

Spilogale putorius (Eastern Spotted Skunk) is a small, secretive carnivore that has substantially declined throughout the eastern United States since the mid-1900s. To better understand the current status of Eastern Spotted Skunks, we studied survival and reproduction of the S. p. putorius (Appalachian Spotted Skunk) subspecies across 4 states in the central and southern Appalachian Mountains from 2014 to 2020. Using encounter histories from 99 radio-collared Appalachian Spotted Skunks in a Kaplan–Meier known-fate survival analysis, we calculated a mean annual adult survival rate of 0.58. We did not find support for this survival rate varying by sex, predator cover (canopy cover and topographic ruggedness), or climate. Compared to estimates of survival from previous research, our data suggest that Appalachian Spotted Skunk survival is intermediate to the S. p. interrupta (Plains Spotted Skunk) and S. p. ambarvalis (Florida Spotted Skunk) subspecies of Eastern Spotted Skunk. We located 11 Appalachian Spotted Skunk natal dens and estimated mean litter size to be 2.8 juveniles per female. We used a Lefkovitch matrix to identify the most important demographic rates and found that adult survivorship had the largest impact on the population growth rate. These results provide important demographic information for future Eastern Spotted Skunk population viability analyses and can serve as a baseline for future comparative assessments of the effects of management interventions on the species.

Alabama, North Carolina, South Carolina, Virginia↗

USGS2023

A Fisherman's Tale: An unusual observation of the Ozark Cavefish, Troglichthys (= Amblyopsis) Rosae (Eigenmann)

Troglichthys (= Amblyopsis ) rosae (Ozark Cavefish) is currently known from 83 locations within the Ozark Highlands ecoregion. We found a cavefish at a new location in the Grand Lake O' the Cherokees on the western side of the Neosho River (Delaware County, OK), which is on the northwest periphery of the Ozark Cavefish range. Examination of the mitochondrial ND2 gene supports that the specimen is an Ozark Cavefish, but distinct (4.6–9.2% pairwise distance) from other specimens that have been genetically sampled, and could represent a unique population. Future research should focus on expanding sampling efforts and conducting a range-wide genetic analysis of the Ozark Cavefish.

Southeastern Naturalist↗

USGS2023

A Buteo sp. hawk predates a hummingbird (Trochilidae) during autumn migration

Predation can play a significant role on survival during migration as birds find themselves competing for resources in unfamiliar habitats. Here we describe the first documented observation of a Buteo platypterus (Broad-winged Hawk) predating an Archilochus colubris (Ruby-throated Hummingbird) during autumn migration. To our knowledge, this is the first documented record of any Buteo sp. hawk predating any Trochilidae (hummingbird). While predation on hummingbirds likely represents a minor source of mortality, identifying sources of predation and mortality is important in understanding the risk of migration for any species.

Southeastern Naturalist↗

USGS2023

Dietary niche of three omnivorous turtle species in a northern Florida river: Insights from stable isotope analysis

Macrochelys suwanniensis (Suwannee Alligator Snapping Turtle) coexists with 2 other native large omnivorous turtle species ( Chelydra serpentina [Snapping Turtle] and Trachemys scripta scripta [Yellow-bellied Slider]) in a 9-km section of the Santa Fe River in northern Florida. A major shift in dominant submersed aquatic vegetation prompted us to quantify trophic position and niche overlap among these 3 species. Here, we examine carbon and nitrogen isotopic values of these turtles and their potential food resources within the changing riverine system. We provide evidence of low isotopic niche overlap between M. suwanniensis and C. serpentina , whereas T. s. scripta occupied a discrete niche having lower carbon and nitrogen values.

Florida↗

USGS2023

Condition and coloration of lingual lures of Alligator Snapping Turtles

The lingual lures of Macrochelys (alligator snapping turtles) are believed to be the only prey-capturing lures within the mouths of modern reptiles. To date, no formal assessment of lure condition in Macrochelys has been published, and few researchers record lure data. Herein, we report damaged or missing lures from 25 Macrochelys temminckii (Alligator Snapping Turtle; 7 adults, 18 juveniles) from a sample of more than 2000 lure assessments in 4 states, indicating this is a rare occurrence. We also describe lingual lure color observed in these assessments and introduce standardized terminology and color categories. We suggest researchers record data on the condition and coloration of the lingual lure to further our understanding of this ecological and evolutionary adaptation.

Southeastern Naturalist↗

USGS2024

Updated distribution for two freshwater mussel species of conservation concern in Oklahoma

Qualitative and quantitative sampling efforts in the Verdigris River, OK (upstream of Lake Oologah), yielded new distributional records of 2 freshwater mussel species of conservation need: Cyprogenia aberti (Western Fanshell) and Ptychobranchus occidentalis (Ouachita Kidneyshell). The Ouachita Kidneyshell has not been documented alive during a scientific survey in the Oklahoma portion of the Verdigris River in nearly 100 years. Our observations extend the known distribution for the Western Fanshell further downstream into Oklahoma by ∼36 river km. These findings indicate an expansion in the known range and potential improvement in the populations of 2 imperiled mussel species, contrary to the prevailing global trend of mussel population decline.

Oklahoma↗