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At least 919 records · Page 51Linked to original sources

USGS2017

Novel observations of larval fire survival, feeding behavior, and host plant use in the regal fritillary, Speyeria idalia (Drury) (Nymphalidae)

Speyeria idalia is a prairie specialist that has experienced dramatic population declines throughout its range. Speyeria idalia is nearly extirpated from the eastern portion of its former range; however, populations within Kansas are relatively stable. We made several previously undescribed field observations of late-instar larvae and post-diapause female S. idalia in northeastern Kansas during 2014–2016. We report finding late-instar larvae at locations that were burned within weeks of detection. The observations of larvae shortly following a burn suggests that S . idalia larvae are capable of surviving fire and contradicts our current knowledge of this species. Additionally, we describe a feeding behavior characteristic of late-instar larvae. Larvae observed in the field and lab stripped leaves of host plants leaving only stems. This strip-style feeding behavior provided unique feeding evidence that was valuable to detecting the presence of larvae in the field. Finally, we documented larvae and post-diapause, egg depositing females using Viola sororia. The use of this relatively widespread and common plant by S. idalia populations in the Central Great Plains has only been implicitly documented but may have important conservation implications. These novel observations further our knowledge of the ecology of this imperiled species and provide timely information that may improve research and conservation management efforts directed toward S . idalia populations.

Journal of the Lepidopterists' Society↗

USGS2001

Establishment of two invasive crustaceans (Copepoda: Harpacticoida) on the nearshore sands of Lake Michigan

Benthic copepods (Copepoda: Harpacticoida) in the nearshore sediments of southern Lake Michigan appear to be dominated by two new invasive species. We report the first occurrence in North America of Schizopera borutzkyi Montschenko, a native to the Danube River delta, and Heteropsyllus nr. nunni, likely a new species that is morphologically similar to the marine species Heteropsyllus nunni and represents the first occurrence of this genus in freshwater. Schizopera borutzkyi is a euryhaline species occurring in shallow sands in its native habitat and in deeper sands (6-15 m) in southern Lake Michigan. Based on the absence of these species from previous studies, we suggest that they are recent introductions. Heteropsyllus nr. nunni dominated (55-100%) the harpacticoid abundance to depths of 9 m, but S. borutzkyi comprised 75% of the harpacticoid abundance at 15 m. Native harpacticoids were always greatly outnumbered by invasive harpacticoids in our samples, which suggests that the natives are being replaced rapidly or that the invasive species are finding unused resources. The ecological implications of these introductions are not known, but these invasions may represent continued 'invasional meltdown' in Lake Michigan.

Canadian Journal of Fisheries and Aquatic Sciences↗

USGS1998

Ecology of Siberian Taimen Hucho taimen in the Lake Baikal Basin

Taimen Hucho taimen historically inhabited most tributaries and littoral areas of Lake Baikal, in south central Siberia, where they supported subsistence and commercial fisheries. Logging, pollution, and overfishing have caused dramatic population declines or local extinction of most stocks. Most of what is known about this species has been published in eastern journals and therefore is not readily available to western scientists. New data collected during the 1980s and 1990s have been combined with other reports to provide an overview of the biology and life history of this species. Taimen are long-lived fish and can reach ages of 29 years and sizes up to 60 kg. Populations can either be strictly riverine or anadromous. Adults from both life histories ascend rivers in spring to spawn and feed, and less extensive migrations occur in fall to prey on spawning omul ( Coregonus autumnalis migratorius ). Principal food items for age 1 and 2 taimen are macroinvertebrates, but young taimen quickly become piscivorous at age 2 when they consume mainly black Baikal grayling ( Thymallus arcticus baicalensis ), and sculpins ( Taracottus kneri, Cottus kesslerij ). Males reach sexual maturity at ages 7 to 8 and later for females at ages 8 to 9. Average egg production per female was about 22,000 eggs. Parasite burdens are heavy but composed of few species and mediated by prey items consumed. This fish is a highly-specialized predator and plays an indispensable role in the structure of fish communities in mountains and foothills. Taimen conservation in the Baikal region is impossible without adoption and implementation of a dedicated rehabilitation program that includes the protection of remaining populations and habitat, and possibly introduction of hatchery-reared fish in selected areas where habitat remains, but parental stocks are low.

Journal of Great Lakes Research↗

USGS2026

The Great Lakes aquatic tissue analysis repository (GLATAR)

Empiricists and modellers use information on energy density, proximate composition, stable isotopes, fatty acids, thiamine, and bioaccumulative tracers (e.g., PCBs and mercury) to understand the state and inter-relationships of aquatic food webs. Data exist in many published and unpublished sources, but are not consolidated in an easily accessible database that would serve as a vital resource to i) provide basic estimates of these diet-derived measures of body composition, ii) understand sources of variation in the underlying data, iii) facilitate exploration and development of data proxies, and iv) assist in study design. We designed GLATAR (Great Lakes Aquatic Tissue Analysis Repository, glatar.org ) to address this need. GLATAR is an open-access, searchable database linked to a web-based toolbox to visualise and generate user-defined summaries on diet-derived ecological metrics, with a focus on taxa of importance to the Great Lakes. GLATAR currently contains over 50,000 records on energy density, chemical tracers, and proximate body composition from 67 species of fish and 72 invertebrate taxa. We hope this user-friendly interface will entice others to upload their published and unpublished data to the repository, enriching the breadth of data accessible to researchers. In this way, GLATAR will become a ‘living’ and interactive resource for empiricists and modellers working in freshwater ecosystems as they make critical decisions related to growth, production, and consumption across a diverse group of economically and ecologically important aquatic species.

Journal of Great Lakes Research↗

USGS1996

Grazing trails formed by soldier fly larvae (Diptera: Stratiomyidae) and their paleoenvironmental and paleoecological implications for the fossil record

Recent trails formed by soldier fly larvae (Díptera: Stratiomyidae) were examined in a shallow pond in the floodplain of a braided river in Jujuy Province, northwestern Argentina. Collected specimens were identified as Stratiomys convexa van der Wulp. Simple, irregularly meandering trails were produced across the surface of a muddy‐silty substrate. Since soldier fly larvae extend their caudal respiratory tube to the water‐air interface, they are restricted to extremely shallow water. The presence of benthic algal remains within the mouthparts of the larvae suggests a feeding habit of algal grazing. If preserved, these trails would be included in the ichno‐genus Helminthopsis, a common element in ancient freshwater ichno‐faunas. Helminthopsis preserved in pond and lacustrine margin deposits younger than Late Jurassic is regarded as one possible trace fossil analogue of the trails documented herein. Additionally, it is suggested that larvae of many aquatic Diptera with similar ecologic restrictions are potential tracemakers of Helminthopsis and other simple trails in these environments, particularly in post‐Paleozoic deposits. Studies of modern shallow aquatic habitats and reex‐amination of the ichnologic record stress the importance of fly larvae as tracemakers in lake margin and pond ecosystems. Ecologic requirements of soldier fly larvae make them inappropriate analogues of Helminthopsis tracemakers in deeper water, lacustrine settings.

Ichnos: An International Journal for Plant and Ani↗

USGS2016

Challenge to the model of lake charr evolution: Shallow- and deep-water morphs exist within a small postglacial lake

All examples of lake charr ( Salvelinus namaycush ) diversity occur within the largest, deepest lakes of North America (i.e. > 2000 km 2 ). We report here Rush Lake (1.3 km 2 ) as the first example of a small lake with two lake charr morphs (lean and huronicus). Morphology, diet, life history, and genetics were examined to demonstrate the existence of morphs and determine the potential influence of evolutionary processes that led to their formation or maintenance. Results showed that the huronicus morph, caught in deep-water, had a deeper body, smaller head and jaws, higher eye position, greater buoyancy, and deeper peduncle than the shallow-water lean morph. Huronicus grew slower to a smaller adult size, and had an older mean age than the lean morph. Genetic comparisons showed low genetic divergence between morphs, indicating incomplete reproductive isolation. Phenotypic plasticity and differences in habitat use between deep and shallow waters associated with variation in foraging opportunities seems to have been sufficient to maintain the two morphs, demonstrating their important roles in resource polymorphism. Rush Lake expands previous explanations for lake charr intraspecific diversity, from large to small lakes and from reproductive isolation to the presence of gene flow associated with strong ecological drivers.

Biological Journal of the Linnean Society↗

USGS1997

Intestinal helminths of river otters ( Lutra canadensis ) from the Pacific Northwest

The intestinal helminth fauna of river otters, Lutra canadensis, from the Pacific Northwest was characterized by low species richness and intensity of infection. River otters from the lower Columbia River (n = 23) were infected with 9 species of helminths (83% prevalence); those from a relatively undisturbed reference area near the headwaters of the Trask and Wilson rivers on the Oregon coast (n = 6) were infected by 5 species of helminths (100% prevalence). Single species of Eucestoda (Schistocephalus solidus), Digenea (Euparyphium inerme), Acanthocephala (Corynosoma strumosum), and 8 species of Nematoda (Strongyloides lutrae; larvae of Eustrongylides sp., Anisakis sp., and Contracaecum sp.; 3 of Cystidicolidae, and Hedruris sp.) were collected. Most species are typical of piscine definitive hosts and were present as incidental parasites of river otters. Notably, specimens of Euparyphium inerme are reported for the first time in river otters from North America; occurrence of other helminths constitutes new host or geographic records for parasites in river otters in Oregon and Washington. Parasites with marine life cycles were acquired by river otters in freshwater habitats at a great distance from the ocean. The helminth fauna of river otters in the Pacific Northwest was influenced primarily by ecological factors and was indicative of eclectic food habits and the relatively extensive home ranges occupied by these mustelids.

Journal of Parasitology↗

USGS2024

Digging into detectability: Uncovering how temperature influences detection probability of the fossorial Temblor legless lizard

Knowledge of species distributions is critical for conservation, but surveying for rare, understudied species presents many challenges. A two-phase occupancy study can increase knowledge gained from early occupancy studies of a species by quickly using data from the first survey period to revise the study design for a second period. The Temblor legless lizard Anniella alexanderae is a recently described fossorial species found in the southwestern San Joaquin Valley, California, and its status is currently under review by state and federal wildlife agencies. As a fossorial species that is rarely surface active, Temblor legless lizards might be unavailable for detection at certain times of year or under inhospitable conditions (e.g., hot, dry weather), indicating the importance of accounting for false-negative surveys when determining its distribution. We used a multiscale occupancy model to disentangle detection probability, availability for detection, and occupancy for Temblor legless lizards. Focusing our effort from mid-February to mid-April when temperatures are mild and soil moisture is expected to be higher near the surface, we surveyed a total of 89 sites in 2022 ( n = 60) and 2023 ( n = 68) and detected Temblor legless lizards at 12 sites, including 5 new localities. Detection probability was positively related to temperature during our late winter-early spring survey period, and availability for detection was consistently high with minimal fluctuation within each year. Nevertheless, repeated surveys with nondetection can increase confidence that this fossorial lizard does not occur at a site. Temblor legless lizards were more likely to occur at sites near ephemeral streams and in areas without high clay soil content, but more investigation could help to discern drivers of occurrence. Our study provides valuable information for optimizing surveys for Temblor legless lizards and suggests promising directions for future research on this species’ ecology.

California↗

USGS2005

An assessment of Idaho's wildlife management areas for the protection of wildlife

Since 1940, Idaho Department of Fish and Game has developed a network of 31 Wildlife Management Areas (WMAs) across the state. This program has been focused mostly on conservation of game species and their habitats. We assessed the contribution of Idaho's WMAs to conservation of all Idaho's wildlife and other aspects of ecological diversity. Predicted occurrences of species' breeding habitats and other data were used to evaluate the representation of wildlife habitat and other ecological conditions. We found 33 of 39 natural land cover types were mapped as occurring in WMAs. WMAs occurred in 10 of 15 of Bailey's ecoregion sections, absent only from two sections that occupy greater than 1% of Idaho. Percent area of WMAs by elevation followed a pattern similar to percent area of Idaho; however, mean elevation for WMAs was lower than for the state and other protected areas in Idaho. We predicted breeding habitat for 98.4% of Idaho's wildlife and all federal and state listed threatened, endangered, or candidate terrestrial vertebrates to occur in at least one WMA. We predicted habitat for 39 species to occur on five or fewer WMAs, and predicted no habitat on WMAs for five species. We found that a system of WMAs established mainly to protect game species potentially conserves many other aspects of Idaho's ecological diversity, may provide habitat for more than 98% of Idaho's wildlife, and complements other protected areas in the state.

Idaho↗

USGS2012

Bibliography of Dreissena polymorpha (zebra mussels) and Dreissena rostriformis Bugensis (QUAGGA mussels): 1989 to 2011

Dreissenid mussels invaded and colonized waters of the Laurentian Great Lakes during the late 1980s. Their colonization and resulting impact have been characterized as one of the most important ecological changes in freshwater systems in North America. The need for information on dreissenid mussels has grown during the past 2 decades, which has prompted the compilation of this bibliography. Two previous bibliographies of dreissenid mussels indicate average publication rates were 6 publications/year between 1771 and 1964 (1,180 in 194 y) and 30 publications/year between 1964 and 1993 (885 in 30 y). In the current bibliography, the average rate of publication doubled during the past 23 y (1989 to 2011) to 66 publications/year based on a total of 1,502 publications. These rates may be biased by increased numbers of researchers and journals over time but, at a minimum, these rates indicate continued interest and concern by humans about the impact of dreissenid mussels on water availability and the expanding range of dreissenids throughout the world. The current bibliography has a 94% efficiency rate for subject and 100% efficiency for title search criteria when compared with references in published studies of dreissenid mussels in 2011. In addition to publications, we included 206 student theses and 225 chapters in 26 books including 6 books devoted solely to dreissenid mussels. A vast majority of student theses were about dreissenid mussels in North America, especially in the Laurentian Great Lakes. The 6 books devoted to dreissenid mussels contained a variety of chapters that described biology, impact, control, and ecology of dreissenid mussels in both Europe (published in 1992 and 2010) and North America (1993, 1994, 1997, and 2000). In addition, there is a 7th book devoted solely to dreissenid mussels that is near completion.

Journal of Shellfish Research↗

USGS2013

Body and diet composition of sympatric black and grizzly bears in the Greater Yellowstone Ecosystem

The Greater Yellowstone Ecosystem (GYE) has experienced changes in the distribution and availability of grizzly bear (Ursus arctos) food resources in recent decades. The decline of ungulates, fish, and whitebark pine seeds (Pinus albicaulis) has prompted questions regarding their ability to adapt. We examined body composition and diet of grizzly bears using bioelectrical impedance and stable isotopes to determine if 1) we can detect a change in diet quality associated with the decline in either ungulates or whitebark pine, and 2) the combined decline in ungulates, fish, and pine seeds resulted in a change in grizzly bear carrying capacity in the GYE. We contrasted body fat and mass in grizzly bears with a potential competitor, the American black bear (Ursus americanus), to address these questions. Grizzly bears assimilated more meat into their diet and were in better body condition than black bears throughout the study period, indicating the decline in ungulate resources did not affect grizzly bears more than black bears. We also found no difference in autumn fat levels in grizzly bears in years of good or poor pine seed production, and stable isotope analyses revealed this was primarily a function of switching to meat resources during poor seed-producing years. This dietary plasticity was consistent over the course of our study. We did not detect an overall downward trend in either body mass or the fraction of meat assimilated into the diet by grizzly bears over the past decade, but we did detect a downward trend in percent body fat in adult female grizzly bears after 2006. Whether this decline is an artifact of small sample size or due to the population reaching the ecological carrying capacity of the Yellowstone ecosystem warrants further investigation.

Idaho, Montana, Wyoming↗

USGS2012

Book review: The requisite reference for the study of Sirenia

Sirenians often are given little or no notice in texts on marine mammals; whales, dolphins, and seals are what come to mind for most when a marine mammal is imagined. An order of only four extant species, the Sirenia is indeed the “other” frequently overlooked group of marine mammals. Dugongs and manatees remain unknown by much of the world, but to those that study these species, the members are extraordinarily unique and fascinating. The three highly respected authors of this newly published volume are all distinguished researchers, with more than a century of combined expertise in the study of this mammalian order. Their collective experience and insight make this book a captivating and valuable read for students, professionals, and anyone interested in having an all-inclusive reference for learning about the Order Sirenia. Review info: Ecology and conservation of the Sirenia-dugongs and manatees . By H. Marsh, T. J. O'Shea, and J. E. Reynolds, III, 2012. ISBN: 978-0521888288, 521 pp.

Journal of Mammalian Evolution↗

USGS2021

Slimy sculpin depth shifts and habitat squeeze following the round goby invasion in the Laurentian Great Lakes

The collapse of Diporeia spp. and invasions of dreissenid mussels (zebra, Dreissena polymorpha ; quagga, D. bugensis ) and round goby ( Neogobius melanostomus ) have been associated with declines in abundance of native benthic fishes in the Great Lakes, including historically abundant slimy sculpin ( Cottus cognatus ). We hypothesized that as round goby colonized deeper habitat, slimy sculpin avoided habitat competition, predation, and aggression from round goby by shifting to deeper habitat. Accordingly, we predicted increased depth overlap of slimy sculpin with both round goby and deepwater sculpin ( Myoxocephalus thompsonii ) that resulted in habitat squeeze by both species. We used long-term bottom trawl data from Lakes Michigan, Huron, and Ontario to evaluate shifts in slimy sculpin depth and their depth overlap with round goby and deepwater sculpin. Lake Huron most supported our hypotheses as slimy sculpin shifted to deeper habitat coincident with the round goby invasion, and depth overlap between slimy sculpin and both species recently increased. Slimy sculpin depth trends in Lakes Michigan and Ontario suggest other ecological and environmental factors better predicted sculpin depth in these lakes.

Lake Huron, Lake Michigan, Lake Ontario↗

USGS2001

Lake-wide distribution of Dreissena in Lake Michigan, 1999

The Great Lakes Science Center has conducted lake-wide bottom trawl surveys of the fish community in Lake Michigan each fall since 1973. These systematic surveys are performed at depths of 9 to 110 m at each of seven index sites around Lake Michigan. Zebra mussel ( Dreissena polymorpha ) populations have expanded to all survey locations and at a level to sufficiently contribute to the bottom trawl catches. The quagga ( Dreissena bugensis ), recently reported in Lake Michigan, was likely in the catches though not recognized. Dreissena spp. biomass ranged from about 0.6 to 15 kg/ha at the various sites in 1999. Dreissenid mussels were found at depths of 9 to 82 m, with their peak biomass at 27 to 46 m. The colonization of these exotic mussels has ecological implications as well as potential ramifications on the ability to sample fish consistently and effectively with bottom trawls in Lake Michigan.

Journal of Great Lakes Research↗

USGS2026

A survey of the Lake Superior cisco complex using integrated morphological and genetic tools reveals a presumed extinct species, Shortnose Cisco (Coregonus reighardi)

Throughout the 19th and 20th centuries, anthropogenic activities resulted in losses of ciscoes in the Laurentian Great Lakes (LGL) and only Lake Superior was left with a relatively intact complex. In 1929, W. Koelz described six cisco species from Lake Superior: Coregonus artedi, C. hoyi, C. kiyi, C. zenithicus, C. reighardi , and C. nigripinnis . Of these, C. artedi, C. hoyi , and C. kiyi remain abundant in Lake Superior, C. zenithicus is considered extirpated throughout the LGL except in Lake Superior, and reighardi and nigripinnis are considered extinct. We present results reaffirming the presence of C. artedi, C. hoyi , and C. kiyi , and the presence of the presumed extinct C. reighardi. Our analysis did not confirm the presence of C. zenithicus and C. nigripinnis . The principal morphological characters that distinguish C. artedi, C. hoyi, C. kiyi , and C. reighardi reflect habitat and trophic specialization: eye size, gillraker length, and gillraker spacing. The discovery of C. reighardi is expected to stimulate conservation and restoration of rare ciscoes in the LGL, and our integrated morphological and genetic approach can provide insights into the evolution, diversity, and ecology of ciscoes.

Lake Superior↗

USGS1999

Transport, retention, and ecological significance of woody debris within a large ephemeral river

The spatiotemporal patterns and ecological significance of the retention of coarse particulate organic matter and large woody debris have been intensively studied in perennial rivers and streams but are virtually unknown in ephemeral systems. We examined the influence of 2 features characteristic of ephemeral systems, downstream hydrologic decay and in-channel tree growth, on the distribution, transport, and retention of woody debris following a flood having a ∼2.6-y recurrence interval in the ephemeral Kuiseb River in southwestern Africa. A total of 2105 pieces of wood were painted at 8 sites along the river channel to measure retention patterns. The flood had a peak discharge of 159 m<sup>3</sup>/s at the upper end of the study area, decaying to <1 m<sup>3</sup>/s by 200 km downstream. Downstream export of wood from marking sites totaled 59.5% (n = 1253). Transport distances ranged from 1 to 124 km, and 34.8% (n = 436) of the exported wood was recovered. Marked wood retained within marking sites was significantly longer than exported wood (p < 0.001, t-test). Once in transport, there was little correlation between wood length and distance traveled (r = 0.11, correlation analysis, n = 369). Length influenced the site of retention; material retained on debris piles was significantly longer than that stranded on channel sediments (p < 0.001, t-test). In-channel growth of Faidherbia trees significantly influenced wood retention; 83.7% of marked wood not moved by the flood was associated with debris piles on Faidherbia trees. Similarly, 65% of the exported wood retained within downstream debris piles was associated with Faidherbia trees. In contrast to many perennial systems, we observed a general increase in wood retention downstream, peaking in the river's lower reaches in response to hydrologic decay. Debris piles induced sediment deposition and the formation of in-channel islands. Following flood recession, debris piles and their associated sediments provided moist, organic-rich microhabitats, which were focal points for decomposition and secondary production, mimicking patterns reported from the channels of perennial streams and rivers. The ecological significance of retentive obstacles and associated organic debris is a feature common to all fluvial ecosystems, irrespective of their hydrologic regime.

Journal of the North American Benthological Societ↗

USGS2015

Role of ground ice dynamics and ecological feedbacks in recent ice wedge degradation and stabilization

Ground ice is abundant in the upper permafrost throughout the Arctic and fundamentally affects terrain responses to climate warming. Ice wedges, which form near the surface and are the dominant type of massive ice in the Arctic, are particularly vulnerable to warming. Yet processes controlling ice wedge degradation and stabilization are poorly understood. Here we quantified ice wedge volume and degradation rates, compared ground ice characteristics and thermal regimes across a sequence of five degradation and stabilization stages and evaluated biophysical feedbacks controlling permafrost stability near Prudhoe Bay, Alaska. Mean ice wedge volume in the top 3 m of permafrost was 21%. Imagery from 1949 to 2012 showed thermokarst extent (area of water-filled troughs) was relatively small from 1949 (0.9%) to 1988 (1.5%), abruptly increased by 2004 (6.3%) and increased slightly by 2012 (7.5%). Mean annual surface temperatures varied by 4.9°C among degradation and stabilization stages and by 9.9°C from polygon center to deep lake bottom. Mean thicknesses of the active layer, ice-poor transient layer, ice-rich intermediate layer, thermokarst cave ice, and wedge ice varied substantially among stages. In early stages, thaw settlement caused water to impound in thermokarst troughs, creating positive feedbacks that increased net radiation, soil heat flux, and soil temperatures. Plant growth and organic matter accumulation in the degraded troughs provided negative feedbacks that allowed ground ice to aggrade and heave the surface, thus reducing surface water depth and soil temperatures in later stages. The ground ice dynamics and ecological feedbacks greatly complicate efforts to assess permafrost responses to climate change.

Journal of Geophysical Research F: Earth Surface↗

USGS2026

Contrasting haemosporidian infections in two ecologically distinct wading birds from breeding colonies in the southeastern United States

Wading birds may serve as ideal hosts for avian hemoparasites, as they are long-lived, undertake extensive movements, form dense breeding colonies, and inhabit water-associated environments that support vectors. Although previous studies have reported parasite species and prevalence in various wading bird species, little is known about their associations with bird behavior and life stage. To address this gap, we examined haemosporidian infections in two ecologically distinct species, white ibis ( Eudocimus albus ) and tricolored heron ( Egretta tricolor ), to explore differences in life stage and movement that may explain prevalence differences. We combined blood screening for hemoparasites with satellite tracking data describing birds’ movement patterns. We screened 95 white ibis (67 juveniles and 28 adults or subadults) and 69 tricolored herons (45 juveniles and 24 adults). We detected a single Haemoproteus plataleae lineage in both species, with higher infection prevalence in white ibis (42.1 %) than in tricolored herons (14.5 %). Among white ibis, adults showed a higher prevalence (67.9 %) than juveniles (31.3 %), whereas in tricolored herons, adults had a prevalence of 8.3 % and juveniles 17.8 %. Non-breeding season movement data showed that white ibis used both freshwater and saline habitats across the southeastern United States, which may also serve as habitats for vectors. In contrast, tricolored herons remained mainly along coastal areas, using saline habitats in the southeastern United States and wintering sites in Central America, which may be less favorable for vectors. Overall, white ibis may serve as major reservoirs and sources of reinfection for H. plataleae , whereas tricolored herons may facilitate parasite dispersal between breeding colonies along the coasts of the southeastern United States and wintering areas in Central America. This study presents the first direct comparison of hemoparasite infections in two ecologically distinct wading birds and highlights movement data as key to explaining infection differences, providing a baseline for future studies.

Alabama↗