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Matthew J. Lovallo

Publications and source records attributed to Matthew J. Lovallo.

3 recordsLinked to original sources

Surveillance for diseases, pathogens, and toxicants of muskrat (Ondatra zibethicus) in Pennsylvania and surrounding regions

Using diagnostic data and contemporary sampling efforts, we conducted surveillance for a diversity of pathogens, toxicants, and diseases of muskrats ( Ondatra zibethicus ). Between 1977 and 2019, 26 diagnostic cases were examined from Kansas and throughout the Southeast and Mid-Atlantic, USA. We identified multiple causes of mortality in muskrats, but trauma (8/26), Tyzzer’s disease (5/6), and cysticercosis (5/26) were the most common. We also conducted necropsies, during November 2018—January 2019 Pennsylvania muskrat trapping season, on 380 trapper-harvested muskrat carcasses after the pelt was removed. Tissue samples and exudate were tested for presence of or exposure to a suite of pathogens and contaminants. Gastrointestinal tracts were examined for helminths. Intestinal helminths were present in 39.2% of necropsied muskrats, with Hymenolepis spp. (62%) and echinostome spp. (44%) being the most common Molecular testing identified a low prevalence of infection with Clostridium piliforme in the feces and Sarcocystis spp. in the heart. We detected a low seroprevalence to Toxoplasma gondii (1/380). No muskrats were positive for Francisella tularensis or Babesia spp. Cysticercosis was detected in 20% (5/26) of diagnostic cases and 15% (57/380) of our trapper-harvested muskrats. Toxic concentrations of arsenic, cadmium, lead, or mercury were not detected in tested liver samples. Copper, molybdenum, and zinc concentrations were detected at acceptable levels comparative to previous studies. Parasite intensity and abundance were typical of historic reports; however, younger muskrats had higher intensity of infection than older muskrats which is contradictory to what has been previously reported. A diversity of pathogens and contaminants have been reported from muskrats, but the associated disease impacts are poorly understood. Our data are consistent with historic reports and highlight the wide range of parasites, pathogens and contaminants harbored by muskrats in Pennsylvania. The data collected are a critical component in assessing overall muskrat health and serve as a basis for understanding the impacts of disease on recent muskrat population declines.

Pennsylvania

Resource use by American black bear in suburbia: A landholder step selection approach

Range expansion of American black bear ( Ursus americanus ; bear) and residential development has resulted in a growing presence of bear in suburbia. Suburban landscapes exhibiting patchworks of variable-sized parcels and habitats and owned by landowners with diverse values, can create large areas of suitable habitats with limited public access. These landscapes thereby may limit the effectiveness of hunting as a traditional bear population management tool. Managers require better information regarding suburban landowner attitudes regarding hunting before implementing changes intended to increase bear harvest to management populations. To address this need, in 2013, we surveyed landowners to identify properties that allowed bear hunting in three suburban areas of Pennsylvania where bear sightings have increased. We then used location data obtained for 29 bears equipped with global positioning system (GPS) transmitters from 2010 to 2012 to model their resource selection in the study area. We assessed the influence of hunting access, housing density, land cover, and topographic variables on radio-marked black bear monitored 10 days before, during, and after the bear hunting season. We found that resource selection of radio-marked bear was similar for all three periods and bears selected for forested land in all three seasons and herbaceous cover in the pre- and hunting periods. Resource selection by bears was not influenced by whether land was open or closed to hunting in the pre-hunting and hunting periods, but in the post-hunting period lands not open to hunting had support as the second-best model. All radio-marked bears in our study were vulnerable to harvest. However, they did not change resource selection during the hunting season nor did they avoid areas open to hunting. Integrating human dimension data with bear habitat use studies, especially in suburban landscapes, has the potential to address bear space use and population management needs often overlooked in traditional research designs.

Pennsylvania

Snowshoe hare multi-level habitat use in a fire-adapted ecosystem

Prescribed burning has the potential to improve habitat for species that depend on pyric ecosystems or other early successional vegetation types. For species that occupy diverse plant communities over the extent of their range, response to disturbances such as fire might vary based on post-disturbance vegetation dynamics among plant communities. Although responses of snowshoe hares ( Lepus americanus ) to fire have been studied in conifer-dominated forests in northern parts of the species’ range, there is a lack of information on snowshoe hare habitat use in fire-dependent communities in southern parts of their range. We used global positioning system (GPS) and very high frequency (VHF) radio-collars to monitor the habitat use of 32 snowshoe hares in a scrub-oak ( Quercus ilicifolia )-pitch pine ( Pinus rigida ) barrens complex in northeastern Pennsylvania where prescribed fire has been used for habitat restoration. The area contained stands that underwent prescribed burning 1–6 years prior to our study. Also, we investigated fine-scale determinants of habitat use within stands. We found that regardless of season, hares did not select for areas that had been burned within 6 years prior. Hares primarily used stands of older scrub oak, conifer, or hardwoods, which contained dense understory vegetation and canopy cover. Hare habitat use also was positively associated with stand edges. Our results suggest that hares do not respond to prescribed burning of scrub oak in the short-term. In addition, by focusing on structural determinants of habitat use, rather than broad-scale characteristics such as stand type, management strategies for snowshoe hares can be adapted over the extent of their range despite the multitude of different land cover types across which the species occurs.

Pennsylvania