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USGS2022

Limits to reproduction and seed size-number trade-offs that shape forest dominance and future recovery

The relationships that control seed production in trees are fundamental to understanding the evolution of forest species and their capacity to recover from increasing losses to drought, fire, and harvest. A synthesis of fecundity data from 714 species worldwide allowed us to examine hypotheses that are central to quantifying reproduction, a foundation for assessing fitness in forest trees. Four major findings emerged. First, seed production is not constrained by a strict trade-off between seed size and numbers. Instead, seed numbers vary over ten orders of magnitude, with species that invest in large seeds producing more seeds than expected from the 1:1 trade-off. Second, gymnosperms have lower seed production than angiosperms, potentially due to their extra investments in protective woody cones. Third, nutrient-demanding species, indicated by high foliar phosphorus concentrations, have low seed production. Finally, sensitivity of individual species to soil fertility varies widely, limiting the response of community seed production to fertility gradients. In combination, these findings can inform models of forest response that need to incorporate reproductive potential.

Nature Communications↗

USGS1993

Reproductive characteristics of a population of the washboard mussel Megalonaias nervosa (Rafinesque 1820) in the upper Mississippi River

We examined monthly and age-specific gametogenic development of the washboard mussel, Megalonaias nervosa , from April 1986 to March 1987 in navigation Pool 10 of the upper Mississippi River. We found M. nervosa to be a late tachytictic breeder. Female marsupia contained eggs or glochidia primarily from August (17°C) through October (9°C). Males were mature from July through October. Most females released their glochidia in October. Only one female was gravid in November (3°C). Most mussels were sexually mature at 8 years of age and then had an estimated average size of 68 mm (shell height). Only 8% of individuals ≤ 4 years of age showed any degree of reproductive development, while > 90% of age 5 and older individuals had recognizable reproductive material present. In host specificity studies, we verified three fish species as hosts for the glochidial stage. Green sunfish ( Lepomis cyanellus ), black bullhead ( Ictalurus melas ), and channel catfish ( Ictalurus punctatus ) produced juveniles after 26–28 days at 17°C. White suckers ( Catastomus commersoni ) and yellow perch ( Perca flavescens ) retained glochidia from 23 up to 26 days, but no juveniles were produced. Glochidia remained attached to common carp ( Cyprinus carpio ) and fathead minnows ( Pimephales promelas ) ≤ 3 days. Channel catfish were retested at 12°C and produced juveniles after 56 days.

Journal of Freshwater Ecology↗

USGS1983

Clutch size, reproductive success, and organochlorine contaminants in Atlantic coast black-crowned night-herons

In 1979, we gathered clutch-size and reproductive-success data on Black-crowned Night-Herons ( Nycticorax nycticorax ) nesting in three New England and two North Carolina colonies. In 1975, we gathered similar data from one of the New England and one of the North Carolina colonies. Latitudinal differences in clutch initiation were not evident. Mean clutch size was larger in the New England than in the North Carolina colonies. Mean clutch size was smaller in late nests from one New England colony studied in both years and another New England colony studied in 1979; seasonal trends in clutch size for other colonies were not found. In 1979, nest success was greater in two New England colonies than in one North Carolina colony. Within-season differences in nest success occurred but were inconsistent among colonies. In the four instances where statistical comparisons could be made, larger clutches were more successful than smaller ones in two colonies; large and small clutches had similar success in two other colonies. One egg was collected from each of several nests in each colony in 1979 for organochlorine contaminant analysis, and the fate of the remaining eggs was recorded. Concentrations of DDE and PCBs did not differ with clutch size; concentrations of PCBs were lower, however, in eggs laid late in the season. Although the data suggest an effect of DDE on hatching success in the northern more contaminated colonies, the impact of environmental contaminants on overall reproductive success appears to be minimal.

Massachusetts, North Carolina, Rhode Island↗

USGS2005

Interaction of rearing environment and reproductive tactic on gene expression profiles in Atlantic salmon

Organisms that share the same genotype can develop into divergent phenotypes, depending on environmental conditions. In Atlantic salmon, young males of the same age can be found either as sneakers or immature males that are future anadromous fish. Just as the organism-level phenotype varies between divergent male developmental trajectories, brain gene expression is expected to vary as well. We hypothesized that rearing environment can also have an important effect on gene expression in the brain and possibly interact with the reproductive tactic adopted. We tested this hypothesis by comparing brain gene expression profiles of the two male tactics in fish from the same population that were reared in either a natural stream or under laboratory conditions. We found that expression of certain genes was affected by rearing environment only, while others varied between male reproductive tactics independent of rearing environment. Finally, more than half of all genes that showed variable expression varied between the two male tactics only in one environment. Thus, in these fish, very different molecular pathways can give rise to similar macro-phenotypes depending on rearing environment. This result gives important insights into the molecular underpinnings of developmental plasticity in relationship to the environment. ?? 2005 The American Genetic Association.

Conference Paper↗

USGS2024

Lifetime reproductive characteristics of gray wolves

Female and male cooperative breeders can use different strategies to maximize reproduction and fitness over their lifetimes. Answering questions about fitness in cooperative breeders requires long-term studies as well as complete data on group composition and size which can be exceedingly difficult to obtain. Using a long-term genetic data set of complete group pedigrees, I asked how lifetime reproductive characteristics of female and male gray wolves ( Canis lupus ) differed. I predicted that genetic relatedness to helpers would be higher for females than males due to philopatric behavior of female wolves, group size would be similar between the sexes, females would inherit breeding positions from within groups more often than males due to differences in dispersal strategies between the sexes, males would have more lifetime mates and produce more young than females because of polygamy, and females would breed for more years than males due to the likelihood that females would still breed (with a new partner) after a mate died or was expelled from the group. I documented complete lifetime breeding histories for 11 male and 18 female wolves in Idaho, United States, 2008 to 2018. Genetic relatedness to helpers, group size, number of mates, pups, and years breeding did not differ between the sexes. Females, however, inherited breeding positions within groups far more often than males. Individuals who secured breeding positions generally reproduced for 2 seasons and commonly had more than 1 partner during their lifetimes if they were able to maintain their breeding position longer. Direct fitness varied greatly within female and male breeding wolves.

Journal of Mammalogy↗

USGS2020

Revealing migration and reproductive habitat of invasive fish under an active population suppression program

Endemic species face a variety of threats including predation from non‐native invaders. In some cases, however, invasive species can be managed by directly suppressing populations, and tracking technologies that allow researchers to identify movement patterns and aggregations representative of the population can facilitate suppression activities. In Yellowstone Lake (Yellowstone National Park, Wyoming), invasive lake trout ( Salvelinus namaycush ) have been the target of a population suppression program for over two decades. For this form of management, the reproductive period is particularly important because fish migrate to and from spawning grounds. From 2011 to 2014, adult lake trout ( n = 317) in Yellowstone Lake were tracked using acoustic biotelemetry. After controlling for spatial and temporal dependency in the data, total abundance of unique individuals was estimated where migratory trajectories occurred at confirmed spawning sites. Aggregations and migratory trajectories were further estimated at locations where spawning had not previously been observed. Across years, the greatest number of individuals was observed along a migration corridor in the southwestern area of the lake. Novel strategies for analyzing acoustic telemetry data provided insights into the behavior of an invasive fish species. By betraying the positions of conspecifics, tagged fish revealed potentially important reproductive habitats and migration corridors that warranted further investigation as possible sites for population suppression.

Wyoming↗

USGS2018

Chasing a changing climate: Reproductive and dispersal traits predict how sessile species respond to global warming

Aim Studies of species' range shifts have become increasingly relevant for understanding ecology and biogeography in the face of accelerated global change. The combination of limited mobility and imperilled status places some species at a potentially greater risk of range loss, extirpation or extinction due to climate change. To assess the ability of organisms with limited movement and dispersal capabilities to track shifts associated with climate change, we evaluated reproductive and dispersal traits of freshwater mussels (Unionida), sessile invertebrates that require species‐specific fish for larval dispersal. Location North American Atlantic Slope rivers. Methods To understand how unionid mussels may cope with and adapt to current and future warming trends, we identified mechanisms that facilitated their colonization of the northern Atlantic Slope river basins in North America after the Last Glacial Maximum. We compiled species occurrence and life history trait information for each of 55 species, and then selected life history traits for which ample data were available (larval brooding duration, host fish specificity, host infection strategy, and body size) and analysed whether the trait state for each was related to mussel distribution in Atlantic Slope rivers. Results Brooding duration ( p < .01) and host fish specificity ( p = .02) were significantly related to mussel species distribution. Long‐term brooders were more likely than short‐term brooders to colonize formerly glaciated rivers, as were host generalists compared to specialists. Body size and host infection strategy were not predictive of movement into formerly glaciated rivers ( p > .10). Main conclusions Our results are potentially applicable to many species for which life history traits have not been well‐documented, because reproductive and dispersal traits in unionid mussels typically follow phylogenetic relationships. These findings may help resource managers prioritize species according to climate change vulnerability and predict which species might become further imperilled with climate warming. Finally, we suggest that similar trait‐based decision support frameworks may be applicable for other movement limited taxa.

Diversity and Distributions↗

USGS2016

Off-road vehicles affect nesting behaviour and reproductive success of American Oystercatchers Haematopus palliatus

As human populations and associated development increase, interactions between humans and wildlife are occurring with greater frequency. The effects of these interactions, particularly on species whose populations are declining, are of great interest to ecologists, conservationists, land managers and natural resource policy-makers. The American Oystercatcher Haematopus palliatus , a species of conservation concern in the USA, nests on coastal beaches subject to various forms of anthropogenic disturbance, including aircraft overflights, off-road vehicles and pedestrians. This study assessed the effects of these human disturbances on the incubation behaviour and reproductive success of nesting American Oystercatchers at Cape Lookout National Seashore, on the Atlantic coast of the USA. We expanded on-going monitoring of Oystercatchers at Cape Lookout National Seashore by supplementing periodic visual observations with continuous 24-h video and audio recording at nests. Aircraft overflights were not associated with changes in Oystercatcher incubation behaviour, and we found no evidence that aircraft overflights influenced Oystercatcher reproductive success. However, Oystercatchers were on their nests significantly less often during off-road vehicle and pedestrian events than they were during control periods before the events, and an increase in the number of off-road vehicles passing a nest during incubation was consistently associated with significant reductions in daily nest survival (6% decrease in daily nest survival for a one-vehicle increase in the average number of vehicles passing a nest each day; odds ratio = 0.94; 95% confidence interval (CI) 0.90, 0.98) and hatching success (12% decrease in hatching success for a one-vehicle increase in the average number of vehicles passing a nest each day; odds ratio = 0.88; 95% CI 0.76, 0.97). Management of vehicles and pedestrians in areas of Oystercatcher breeding is important for the conservation of American Oystercatchers.

International Journal of Avian Science↗

USGS2022

Ophidiomycosis is related to seasonal patterns of reproduction, ecdysis, and thermoregulatory behavior in a free-living snake species

Informed and effective management of emerging infectious diseases can be improved by a clear understanding of host–pathogen–environment interactions. Impacts of the seasonal environment on pathogen dynamics and host responses are poorly described in most reptile host–fungal pathogen systems. Here, we describe seasonal patterns of ophidiomycosis, a disease caused by the fungus Ophidiomyces ophidiicola ( Oo ), in a population of pygmy rattlesnakes, Sistrurus miliarius , in central Florida. We used field observations of gross clinical signs of disease in combination with qPCR on skin swabs to examine the seasonal prevalence of Oo and patterns of clinical presentation in hosts. We monitored thermoregulatory behaviors, ecdysis, and reproductive status in free-living snakes to examine seasonal associations between infection and host coping responses. Both the prevalence of Oo and clinical signs of disease varied strongly with the season (winter high and summer low). In both seasons, the presence of clinical signs was a strong predictor of the presence of Oo as identified by qPCR on skin swabs (78% probability across seasons). Snakes with clinical signs of disease were more likely to be observed exhibiting thermoregulatory behavior or in ecdysis compared to non-clinical snakes across seasons. The prevalence of Oo was not significantly different in pregnant snakes compared to other reproductive categories, but pregnant females were less likely to exhibit clinical signs of disease compared to males. Our results highlight strong seasonal patterns in both host clinical signs and Oo prevalence and support the efficacy of using gross clinical signs of disease in combination with qPCR on skin swabs to assess disease dynamics in free-living snakes. We also identify ecdysis and thermoregulatory behaviors as components of the seasonal disease-coping response and highlight the need to examine these behaviors as potential drivers of seasonal infection outcomes in reptiles afflicted with fungal pathogens.

Journal of Zoology↗

USGS1969

Dieldrin and DDT: Effects on sparrow hawk eggshells and reproduction

Patterns of reproductive failure in declining populations of several European and North American raptorial species were duplicated experimentally with captive American sparrow hawks Falco sparverius that were given a diet containing two commonly used organochlorine insecticides. Major effects on reproduction were increased egg disappearance, increased egg destruction by parent birds, and reduced eggshell thickness.

Science↗

USGS2012

Survival, growth and reproduction of non-native Nile tilapia II: Fundamental niche projections and invasion potential in the northern Gulf of Mexico

Understanding the fundamental niche of invasive species facilitates our ability to predict both dispersal patterns and invasion success and therefore provides the basis for better-informed conservation and management policies. Here we focus on Nile tilapia (Oreochromis niloticus Linnaeus, 1758), one of the most widely cultured fish worldwide and a species that has escaped local aquaculture facilities to become established in a coastal-draining river in Mississippi (northern Gulf of Mexico). Using empirical physiological data, logistic regression models were developed to predict the probabilities of Nile tilapia survival, growth, and reproduction at different combinations of temperature (14 and 30°C) and salinity (0–60, by increments of 10). These predictive models were combined with kriged seasonal salinity data derived from multiple long-term data sets to project the species' fundamental niche in Mississippi coastal waters during normal salinity years (averaged across all years) and salinity patterns in extremely wet and dry years (which might emerge more frequently under scenarios of climate change). The derived fundamental niche projections showed that during the summer, Nile tilapia is capable of surviving throughout Mississippi's coastal waters but growth and reproduction were limited to river mouths (or upriver). Overwinter survival was also limited to river mouths. The areas where Nile tilapia could survive, grow, and reproduce increased during extremely wet years (2–368%) and decreased during extremely dry years (86–92%) in the summer with a similar pattern holding for overwinter survival. These results indicate that Nile tilapia is capable of 1) using saline waters to gain access to other watersheds throughout the region and 2) establishing populations in nearshore, low-salinity waters, particularly in the western portion of coastal Mississippi.

Alabama, Louisiana, Mississippi↗

USGS2020

Extreme mortality and reproductive failure of common murres resulting from the northeast Pacific marine heatwave of 2014-2016

About 62,000 dead or dying common murres ( Uria aalge ), the trophically dominant fish-eating seabird of the North Pacific, washed ashore between summer 2015 and spring 2016 on beaches from California to Alaska. Most birds were severely emaciated and, so far, no evidence for anything other than starvation was found to explain this mass mortality. Three-quarters of murres were found in the Gulf of Alaska and the remainder along the West Coast. Studies show that only a fraction of birds that die at sea typically wash ashore, and we estimate that total mortality approached 1 million birds. About two-thirds of murres killed were adults, a substantial blow to breeding populations. Additionally, 22 complete reproductive failures were observed at multiple colonies region-wide during (2015) and after (2016–2017) the mass mortality event. Die-offs and breeding failures occur sporadically in murres, but the magnitude, duration and spatial extent of this die-off, associated with multi-colony and multi-year reproductive failures, is unprecedented and astonishing. These events co-occurred with the most powerful marine heatwave on record that persisted through 2014–2016 and created an enormous volume of ocean water (the “Blob”) from California to Alaska with temperatures that exceeded average by 2–3 standard deviations. Other studies indicate that this prolonged heatwave reduced phytoplankton biomass and restructured zooplankton communities in favor of lower-calorie species, while it simultaneously increased metabolically driven food demands of ectothermic forage fish. In response, forage fish quality and quantity diminished. Similarly, large ectothermic groundfish were thought to have increased their demand for forage fish, resulting in greater top-predator demands for diminished forage fish resources. We hypothesize that these bottom-up and top-down forces created an “ectothermic vise” on forage species leading to their system-wide scarcity and resulting in mass mortality of murres and many other fish, bird and mammal species in the region during 2014–2017.

PLoS ONE↗

USGS1981

Reproductive tests of diazinon on bobwhite quail

Diazinon was fed at sublethal levels to reproductively active bobwhite (Colinus virginianus). Thirty pairs were given constant concentrations (0, 35. 50, 72, 104, or 150 ppm) for 3 weeks (Constant group). Another 30 pairs (Pair-fed group) were matched to these by body weights and were fed the amounts of untreated food consumed by corresponding Constant pairs to evaluate the effect of food deprivation. To mimic environmental degradation, a group of 30 pairs (Decreasing group) was initially given diazinon at the same concentrations as the Constant group; the concentration was decreased geometrically every 3 days to yield a 50 percent reduction in 15 days. Following 3 weeks of exposure to the experimental diets, pairs were maintained for an additional 3 weeks on untreated food to measure the birds' recovery. Food consumption, egg production, and hatchability were recorded for each pair. Individually hatched chicks were banded and kept for 2 weeks to monitor their survival. Food consumption was negatively dose-related above 35 ppm in the Constant and Decreasing groups. The only reproductive parameter affected was egg production. Production declined as the dose was increased above 35 ppm in the Constant and Decreasing groups. Egg laying was reduced more in the Constant than in the Decreasing pairs. The egg-laying rate of the Constant and Pair-fed groups differed; this difference was reflected by a threshold corresponding to 72 ppm in the Pair-fed group as opposed to 35 ppm in the Constant group. Residual effects of prior treatment on food consumption and egg production were observed in the Constant and Pair-fed pairs during the posttreatment period, but the Decreasing pairs were not influenced by prior treatment. The magnitude of effects related to the dose was not as great during the posttreatment period as during the treatment period and represented the recovery from diazinon effects over the span of the posttreatment period. The schedule of doses for the Decreasing group ameliorated the deleterious effects of diazinon, whereas the dosing schedule for the Constant group yielded a small overestimation of hazard to wildlife.

Book chapter↗

USGS2008

Nutrient-reserve dynamics during egg production by female Greater Scaup (Aythya marila): Relationships with timing of reproduction

We studied nutrient-reserve dynamics of female Greater Scaup ( Aythya marila ) to quantify intraspecific strategies of nutrient acquisition for egg production, particularly in relation to the seasonal timing of reproduction (i.e., date of initiation of rapid follicle growth [RFG]). We collected female Greater Scaup on the Yukon-Kuskokwim Delta, Alaska, from arrival through clutch formation during the 2002 and 2003 breeding seasons, and we subsequently conducted standard proximate body-composition analysis. Endogenous lipid, protein, and mineral reserve levels did not decline during egg production. This result differs from most other nutrient-reserve studies of waterfowl, suggesting that female Greater Scaup rely on exogenous food resources, rather than endogenous nutrient reserves, to meet the energy and nutrient costs of clutch formation. Furthermore, endogenous nutrient-reserve levels did not decline with date of RFG initiation, which indicates that body condition at initiation of egg production was similar across the nesting season. We found evidence of nutrient-reserve thresholds for initiation of RFG, in that lipid, protein, and mineral reserves were smaller in nonreproductive than in reproductive females. In light of recent conservation concerns over declining North American scaup populations, our data contrast with nutrient-reserve dynamics described for Lesser Scaup ( A. affinis ).

The Auk↗

USGS2010

Evaluation of a reproductive index for estimating productivity of grassland breeding birds

Declining populations of grassland breeding birds have led to increased efforts to assess habitat quality, typically by estimating density or relative abundance. Because some grassland habitats may function as ecological traps, a more appropriate metric for determining quality is breeding success, which is challenging to determine for many cryptic-nesting grassland birds. This difficulty led Vickery et al. (1992) to propose a reproductive index based on behavioral observations rather than nest fate. We rigorously evaluated the index for 2 years using a Savannah Sparrow (Passerculus sandwichensis) population in western New York and found a weak correlation in classification of the breeding stages of monitored territories among multiple observers (r = 0.398). We also discovered a large difference between overall territory and nest success rates independently estimated with the index (9.8% over the entire breeding cycle) and with nest searching and monitoring (41.7% of nests successfully fledged young). Most importantly, we made territory-level comparisons of index estimates with actual nest fate and found that the index correctly predicted fates for only 43% of the monitored nests. A Mayfield logistic regression analysis demonstrated that only index rank 4 (eggs hatched, but young failed to fledge) showed a strong positive correlation with nest success. Although the reproductive index may function as a coarse indicator of habitat suitability (e.g., documenting production in potential ecological traps), in our study the index exhibited neither internal consistency nor the ability to predict nest fate at the plot or territory level and functioned poorly as a substitute for nest searching and monitoring. ?? 2010 The American Ornithologists' Union.

The Auk↗

USGS2001

Effects of suspended sediment on the reproductive success of the tricolor shiner, a crevice-spawning minnow

Excessive sedimentation of rivers and creeks has been linked to increasing levels of imperilment in the diverse fish fauna of the southeastern United States. In particular, benthic-spawning fishes have decreased in both numbers and range. The tricolor shiner Cyprinella trichroistia is a crevice-spawning minnow that is widespread in the eastern Mobile River drainage above the Fall Line. While they are less sensitive to perturbation than the federally threatened blue shiner C. caerulea, tricolor shiners have decreased in numbers and range during the past few decades. This experiment examined the effects of 0 (control), 100, 300, and 600 mg/L initial concentrations of suspended sediment on the reproductive success of the tricolor shiner. Increasing levels of suspended sediment caused decreasing levels of reproductive success (fewer spawns and fewer eggs laid when spawning occurred). Increasing levels of suspended sediment also delayed the onset of spawning, resulting in distinct frequency distributions of clear eggs, eyed eggs, and larvae across treatments. Mortality of eggs and larvae was not a factor in the experiment. We examined daily sediment concentration data recorded at three sites in the upper Coosa River over the April-August spawning season of 1963. By weighting our experimental results by the number of days above each sediment concentration, we estimated that 20% fewer eggs were laid than would have been laid if conditions had been like those of the controls. Albeit our model is simplistic, it provides insight into how excessive sedimentation contributes to population extirpation. Mitigation of suspended sediments is an important management action for the conservation of southern Appalachian fishes that spawn in benthic habitats.

Transactions of the American Fisheries Society↗

USGS2007

Reproductive strategies of northern geese: Why wait?

Migration and reproductive strategies in waterbirds are tightly linked, with timing of arrival and onset of nesting having important consequences for reproductive success. Whether migratory waterbirds are capital or income breeders is predicated by their spring migration schedule, how long they are on breeding areas before nesting, and how adapted they are to exploiting early spring foods at northern breeding areas. However, for most species, we know little about individual migration schedules, arrival times, and duration of residence on breeding areas before nesting. To document these relationships in a northern nesting goose, we radiotracked winter-marked Tule Greater White-fronted Geese ( Anser albifrons elgasi ; hereafter “Tule Geese”; n = 116) from the time of their arrival in Alaska through nesting. Tule Geese arrived on coastal feeding areas in mid-April and moved to nesting locations a week later. They initiated nests 15 days (range: 6–24 days) after arrival, a period roughly equivalent to the duration of rapid follicle growth. Tule Geese that arrived the earliest were more likely to nest than geese that arrived later; early arrivals also spent more time on the breeding grounds and nested earlier than geese that arrived later. The length of the prenesting period was comparable to that of other populations of this species, but longer than for goose species that initiate rapid follicle growth before arrival on the breeding grounds. We suggest that Tule Geese nesting in more temperate climates are more likely to delay breeding to exploit local food resources than Arctic-nesting species that may be constrained by short growing seasons.

The Auk↗

USGS2007

Comparison of diet, reproductive biology, and growth of the pig frog (Rana grylio) from harvested and protected areas of the Florida Everglades

Distinct differences in body size exist among three Rana grylio populations in areas of the Florida Everglades that differ in frog harvest pressure and hydroperiod. Frogs from two populations are harvested regularly throughout the year, while those in the third are protected from harvest. We compared seasonal and sex differences in diet, reproduction, and growth across these populations to examine life-history patterns. By volume, crayfish and anurans were the most abundant prey items for all adults across sites. Frogs from drier sites consumed more crayfish than frogs from the wettest site. Anurans were abundant in the diet during the wet season, while crayfish and fish were abundant during the dry season. More frogs with empty stomachs were captured during the wet season than the dry season. Feeding, growth, and fat deposition were greatest during the dry season across all sites. Although females were found in all reproductive stages throughout the year, the highest percentage of females had mature ova during the late dry season and spent ovaries during the early wet season. Individual patterns of growth were similar across all sites and matched historical growth data from the 1950s. Differences in body size among sites were most likely attributable to differential mortality (i.e., harvest pressure, predation) rather than to differences in food access or growth. ?? 2007 by the American Society of Ichthyologists and Herpetologists.

Copeia↗