Islands can be proxies for understanding species-occupancy dynamics—like rates of immigration, extirpation, and persistence—in a world of increasingly isolated habitat patches. These dynamics have been investigated extensively at short and long timescales (e.g., a few versus tens of thousands of years), but intermediate periods are less frequently considered. Here, we report a resurvey of the amphibians and mammals of Charity Island, in Saginaw Bay of Lake Huron, ∼100 years after the island was first surveyed in 1910. We conducted surveys via visual and auditory monitoring, as well as targeted trapping. We found 7 species not previously documented on the island, although it is likely that only Tamias striatus (Eastern Chipmunk), Lithobates catesbeianus (= Rana catesbeiana) (American Bullfrog), and Hyla versicolor (Gray Treefrog) are genuinely new arrivals. In contrast, the previously detected Lepus americanus (Snowshoe Hare), Sylvilagus floridanus (Eastern Cottontail), Anaxyrus americanus (Eastern American Toad), and Lithobates (= Rana) palustris (Pickerel Frog) were not detected in our surveys. These findings indicate that modest but detectable species turnover occurs on isolated, high-latitude islands, even among otherwise common species.

Anticoagulant rodenticides (ARs) are commonly used across the US to control rodent populations but may cause negative effects when secondarily consumed by raptors. Falco sparverius (American Kestrel) is a species of growing conservation concern due to widespread declines. We investigated AR exposure in American Kestrels by testing liver samples from 23 carcasses salvaged in Kentucky during 2014–2018. We confirmed exposure to 1 or more AR compounds in 57% of the birds examined. Rodenticides detected included brodifacoum, bromadiolone, and diphacinone. Brodifacoum was the most commonly detected AR, found in 92% of AR-positive birds. AR exposure was disparate among nestlings from 2 nests. None of the American Kestrels were diagnosed with AR toxicosis, but we found a significant association between poor nutritional condition and AR exposure. Our results indicate that secondary exposure to ARs in American Kestrels warrants more study as a potential contributor to population declines.

The recent invasion of the pheretimoid earthworms in North America, specifically Metaphire hilgendorfi, Amynthas agrestis, and Amynthas tokioensis, commonly referred to as “jumping worms”, has led to an increase in research on their impacts on forest ecosystems, trophic interactions, and soil health. Determining the biomass of earthworms is a fundamental method in studies evaluating the impact of invasion. However, earthworm biomass is highly influenced by moisture content of a particular habitat, thus requiring ash-free dry-mass methods for accurate measurement. This method is time-consuming and results in the destruction of specimens. While an equation exists for Metaphire hilgendorfi, here we present novel allometric equations for converting length to ash-free dry mass for the 2 most common species of the trio, Amynthas agrestis and Amynthas tokioensis. The relationship between length and biomass was significantly different between A. agrestis and A. tokioensis. This relationship was also different for clitellate and non-clitellate A. tokioensis. Sampling site was an important factor in the biomass of A. tokioensis, suggesting that landscape context may be an important driver in the annual growth and development of this species. These allometric equations will support much needed research on the species-specific impacts of these pheretimoid earthworms on native and ornamental plants, soil structure and chemistry, and forest ecosystems.

Many species rely on interspecific interactions during various parts of their life history, including when breeding, acquiring food, and seeking shelter. Here, I make an observation of minnows choosing to associate with one nest-building species over another. I found that when Lepomis megalotis (Longear Sunfish) and L. cyanellus (Green Sunfish) build adjacent nests, minnow nest-associate species were more abundant on the nests of Longear Sunfish. In addition, Longear Sunfish spent more time chasing minnows off their nests than Green Sunfish did. While minnow–sunfish nest-association behavior is well documented, there is little natural history information regarding host preferences. This observation is relevant in setting up hypotheses and formulating questions about these interactions.

The connections between winter and summer habitat for hibernating bats are poorly understood, yet biologists need information on seasonal habitat requirements to aid bats as they recover from white-nose syndrome. We captured and radio-tagged 2 female Perimyotis subflavus (Tricolored Bat) as they emerged from a cave in Pierce County, WI. We lost the signal from one bat shortly after release but successfully radio-tracked the other bat as she flew 51 km to a roost tree on the St. Croix River. The bat made her full spring migration in 1 night on 5 May 2017 and on subsequent nights foraged on the St. Croix River. This record represents only the second published spring emergence tracking attempt for this species and adds to the growing knowledge base of seasonal habitat requirements for understudied bats.

Habitat segregation is a common phenomenon among migratory songbirds during the non-breeding periods of their life cycles, and conservation practices that fail to account for sex or age-based segregation can be ineffective. We evaluated whether segregation occurred among wintering Passerculus sandwichensis princeps (Ipswich Sparrow) latitudinally by capturing birds throughout their winter range and at the patch level by radio-tracking a subset of Ipswich Sparrows on Assateague Island, MD. While sex and age ratios remained similar throughout their winter range, habitat use varied among tracked individuals. The majority of tracked Sparrows were found in areas where both grass and forb cover were available, yet males tended to inhabit locations with additional shrub cover and exhibited larger estimated home ranges than females (mean 50% minimum convex polygon = 2.36 for males vs 0.77 ha for females). Males and adults were more likely to be observed in fore dunes than females and juveniles, which were more likely to be observed in secondary dunes than adults. Distance between the active beach and the nearest vegetated dune influenced seed availability and bird use. Juveniles were located furthest inland where the plants Diodia teres (Poor Joe), Oenothera humifusa (Seabeach Evening Primrose), and Cenchrus tribuloides (Dune Sandbur) were most common. Adults were located nearer the vegetated dune edge, as were the plants Ammophila breviligulata (American Beachgrass), Solidago sempervirens (Seaside Goldenrod), and Panicum amarum (Bitter Panicum). Beach plantings conducted as part of dune-restoration efforts have often been restricted to American Beachgrass, but we suggest incorporating a wider variety of plants to improve habitat for all Ipswich Sparrow age and sex classes.

Lynx rufus (Bobcat) and Lontra canadensis (River Otter) experienced abundance increases and range expansions across the midwestern US after effective management. In response, multiple states allowed legal harvest of both species. In Illinois, Bobcats and River Otters were listed as furbearing game species in 2016 and 2012, respectively; however, little research into how harvest may be affecting these species has been conducted. We used age-at-death data and life-table analyses to determine growth rates (r) and other demographic metrics pre- and post-harvest implementation for both species. We constructed pre-harvest life tables using data from 141 Bobcats (age 0–13 yr) and 165 River Otters (0–12 yr) collected from opportunistic roadkills between 1996 and 2016. We constructed post-harvest life tables using data from 126 Bobcats (age 0–9 yr) and 179 River Otters (age 0–9 yr) collected from roadkills and harvested individuals between 2018 and 2023. Bobcat r was 0.28 in the pre-harvest stage-based life table and 0.08 post-harvest. River Otter r was 0.66 in the pre-harvest stage-based life table and -0.09 post-harvest. After harvest implementation, River Otter population growth declined more than Bobcats. While limited by sample size and sex determination uncertainty, our results corroborate patterns observed in other furbearer populations after harvest implementation. Future statewide abundance research of Bobcats and River Otters may benefit from policies encouraging more hunters and trappers to submit samples and the creation of reliable systems to determine sex.

Human activities have altered natural dispersal patterns of many wildlife species through intentional and accidental translocations. We used population genetics to detect recent long-distance translocations of Procyon lotor (Raccoon) in northeastern North America. Three Raccoons were collected on 2 islands off the US New England coast, with suspected origins in southeastern Canada. We used RADcapture to genotype 1000 microhaplotypes and assign the animals to source locations through comparison to 563 genotypes from the northeastern US and southeastern Canada. The 3 Raccoons assigned to populations associated with the US–Canada border region. Our results add to the sparse scientific literature on Raccoon translocations, highlighting the utility of genetics for detecting long-distance movements of wildlife and implications for disease management.

In 2021, we initiated fieldwork to assess the relative importance of a staging area for Sterna hirundo (Common Tern) at a pier at the confluence of the Patuxent River and Chesapeake Bay, MD. During the post-breeding periods of 2021 through 2023, we resighted 378 banded Common Terns at this staging area, with individuals originating from 6 breeding colonies. Most banded individuals were from Poplar Island, a major nesting site 50 km north of the pier, with up to 37% of that island's annual hatch-year population observed at this staging area. Additionally, biologists have previously observed staging terns at this site, suggesting these observations do not reflect a change in the species' behavior within the region. Cumulatively, our data suggest that this habitat acts as an important staging area for the Chesapeake Bay's Common Tern population, particularly for those nesting on Poplar Island.

Sialia sialis (Eastern Bluebird), a secondary cavity nester, often nests in anthropogenic structures, particularly nest boxes established throughout its range. We describe 3 observations of Eastern Bluebird nests at 2 photovoltaic (PV) solar facilities in eastern New York. At one facility, we observed an open-cup nest on the PV steel support structure, while at another, we observed 2 nests within structures mimicking cavities. At least 2 nests were likely successful. To our knowledge, these are the first documented occurrences of Eastern Bluebird nests within PV solar facilities in the northeastern US. Although further research is needed to determine if successful nesting in PV solar facilities is widespread, our observations suggest that Eastern Bluebirds can nest successfully within these facilities.

The draining of a reservoir in eastern Massachusetts for dam repairs revealed dozens of stumps and several segments of stone walls. We mapped and measured the diameters of all stumps in a 0.1-ha study plot and collected and analyzed tree-ring and wood-anatomy samples from 5 of the stumps. These analyses reconstructed a dense stand of young (<50 years old) Pinus strobus (Eastern White Pine) that recruited during 1826–1848, likely establishing after the site was logged or when the area was no longer used as pasture. Historical accounts indicate that the trees were cut in the fall/ winter of 1873–1874, just prior to the inundation of the reservoir. This opportunistic study provides a snapshot of the mid-19^th-century landscape of southern New England.

Thunnus thynnus (Atlantic Bluefin Tuna) is an opportunistic generalist predator in the pelagic zone of the Atlantic Ocean. In the northwest Atlantic Ocean, Atlantic Bluefin Tuna diets are primarily based on small pelagic prey. Seabirds often prey on the same pelagic forage fish as tuna, leading to an overlap in the timing and location of both seabird and Atlantic Bluefin Tuna foraging activity and the potential for tuna–seabird interactions. Here, we present the first documented evidence of Atlantic Bluefin Tuna consuming a seabird in the Northwest Atlantic Ocean. This is the second report of Atlantic Bluefin Tuna consuming a seabird in the entire species' range. The evidence for this interaction comes from the stomach contents of a commercially harvested Atlantic Bluefin Tuna caught ∼1.6 km offshore of Newfoundland in October 2022. The unknown bird in the Atlantic Bluefin Tuna stomach was identified through DNA metabarcoding as Fratercula arctica (Atlantic Puffin), a diving seabird for which an overlap with pelagic predatory fish is credible. While rarely observed, it is important to identify such interactions between seabirds and predatory fish to gain a more complete understanding of food-web interactions in marine pelagic ecosystems.

Sitta pusilla (Brown-headed Nuthatch) is a songbird of southeastern US pinelands. Since the first New Jersey sighting of the species in 2005, it has been recorded with increasing frequency in the state but had not been found breeding there. I found 2 nesting pairs in Cape May County in 2024 that both successfully fledged young. Further field work could determine if this is an outlier range spillover into uniquely suitable habitat or if the species is expanding further into New Jersey.