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The status of species in freshwater systems shift over time due to natural and anthropogenic causes. Determining the magnitude and cause of these shifts requires a long‐term perspective. This process is complicated when there are also questions about the taxonomic validity of a species. Addressing these issues is important because both can undermine conservation and management efforts if incorrect. Pleurobema riddellii, Louisiana Pigtoe, is under review for protection under the U.S. Endangered Species Act, but its status in the Trinity River basin, where the taxon was described, remains in doubt due to questions about its taxonomy and occurrence within this basin. To address these questions, we compared shell morphometrics of P. riddellii dating to the late Holocene with modern P. riddellii, late Holocene Fusconaia sp., and modern Fusconaia sp. using multivariate analyses to test associations between the putative morphotypes. Based on these analyses, we demonstrate that P. riddellii was likely present in the Trinity during the late Holocene, which indicates questions about its taxonomic validity or presence in this basin are unfounded. Our study further highlights the role zooarchaeological studies can play in status assessments and their utility in better understanding biogeographic patterns for rare species. [ABSTRACT FROM AUTHOR]

Zooarchaeology is the study of animal remains (bone, shell, antler, and other organic tissues) from archaeological sites, which can provide conservation biologists with data on human–environmental interactions with greater time depth than historical records. Such data are of interest because they can be used to study whether or not contemporary animal communities (in this case of freshwater mussels) have changed in terms of species composition or range as a result of human-induced changes to habitat, which is essential for determining a species’ conservation status and formulating actions to protect remaining populations. This study considers whether or not the taxonomic composition of the freshwater mussel community from the Leon River in central Texas differs between the late Holocene and today. Specifically, we analyzed two zooarchaeological assemblages and compared those results with recent surveys conducted within the Leon River. Three species proposed for listing under the Endangered Species Act are found in the zooarchaeological record, of which two are now extirpated from the river basin (Truncilla macrodon and Fusconaia mitchelli). The results of this study provide an example of how zooarchaeological data can be used to evaluate mussel community change through time and provide evidence of range curtailment for threatened mussel species. [ABSTRACT FROM AUTHOR]

Zooarchaeological data are increasingly important for establishing late Holocene conservation baselines for species of concern. The blue sucker ( Cycleptus elongatus) is experiencing range reduction and is endangered in the State of New Mexico. The early historic (ca. AD 1540) distribution of blue sucker is poorly understood, and the extent of habitat loss is unclear. In 1961, two blue sucker skeletal elements were recovered from a late prehistoric/early historic archaeological site in northern New Mexico called Rainbow House (LA 217). Those remains suggest that the past range of blue sucker was larger; however, since that publication, little consideration has been given to the past presence of this species in the Upper Rio Grande. New zooarchaeological data from a site in northern New Mexico called Ponsipa (LA 297) have revealed the presence of multiple blue sucker skeletal elements. Additionally, a review of site reports and regional archaeological journal publications increased the abundance of blue sucker elements found at Rainbow House and added three archaeological sites where blue sucker has been reported in the region. Collectively, this information suggests a broader pre-impoundment distribution for blue sucker than previously recognized and can help establish a new baseline for their conservation or restoration in New Mexico. [ABSTRACT FROM AUTHOR]

Remains of 22 American black bears (Ursus americanus) were excavated from 2 natural trap caves in Missouri during the late 1950s. Age, sex, and size characteristics based on analysis of ursid teeth from the caves corroborates wildlife studies that suggest that subadult to young-adult male bears are relatively vulnerable to accidental deaths in their search for food compared to members of other age-sex cohorts. This information is of interest to wildlife biologists given that North American bears and humans increasingly share habitat. Data on native Missouri black bears are also of general interest because little is known about this population, which was extirpated by the beginning of the twentieth century, and because a reintroduced population is expanding in the southern portion of the state. [ABSTRACT FROM AUTHOR]

Archaeological studies of temporal changes in human predation strategy using foraging theory tend to focus on the role of overexploitation of important prey resources and resulting resource depression. An alternative use of the prey- choice model framed under foraging theory is to investigate the influence of environmental changes, such as increases in climate stress, on prey availability. Environmental change can be expected to produce many of the same effects on human predation strategy as resource depression. Here analytical techniques typically used to study the effects of over-predation and resource depression caused by humans are used to monitor their response to fluctuations in prey availability related to climate change during the Holocene in Missouri. Data and interpretations presented here add to the growing body of zooarchaeological foraging theory literature implicating environmental change as a critical factor in human diet. [ABSTRACT FROM AUTHOR]