Kiana K. G. Koenen

Prevalence of Microsporidia, Cryptosporidium spp., and Giardia spp. in beavers (Castor canadensis) in Massachusetts

Abstract Feces from 62 beavers (Castor canadensis) in Massachusetts were examined by fluorescence microscopy (IFA) and polymerase chain reaction (PCR) for Microsporidia species, Cryptosporidium spp., and Giardia spp. between January 2002 and December 2004. PCR-positive specimens were further examined by gene sequencing. Protist parasites were detected in 6.4% of the beavers. All were subadults and kits. Microsporidia species were not detected. Giardia spp. was detected by IFA from four beavers; Cryptosporidium spp. was also detected by IFA from two of these beavers. However, gene sequence data for the ssrRNA gene from these two Cryptosporidium spp.–positive beavers were inconclusive in identifying the species. Nucleotide sequences of the TPI, ssrRNA, and β-giardin genes for Giardia spp. (deposited in GenBank) indicated that the four beavers were excreting Giardia duodenalis Assemblage B, the zoonotic genotype representing a potential source of waterborne Giardia spp. cysts.

Effects of military operations on behavior and hearing of endangered Sonoran Pronghorn

: Our objectives in this study were to determine whether military activities (e.g., overflight noise, noise from ordnance delivery, ground-based human activity) on the Barry M. Goldwater Range (BMGR) affect the behavior and hearing of Sonoran pronghorn (Antilocapra americana sonoriensis). We contrasted the behavior of pronghorn on BMGR with the closest population of pronghorn in the United States that was not subjected to routine military activity (i.e., on the Buenos Aires National Wildlife Refuge [BANWR], Arizona). Forty percent of the landscape used by the endangered Sonoran pronghorn in the United States is within the 5,739 km2 BMGR, a bombing and gunnery facility in southwestern Arizona. The range of Sonoran pronghorn covers about 88% of BMGR. The 179 Sonoran pronghorn that lived in the United States in December 1992 declined to 99 by December 2000. The Sonoran pronghorn has been listed as endangered for >30 years, but population limiting factors are unknown. Because Sonoran pronghorn use BMGR, land and wildlife managers raised concerns about the potential effects of military activities on the population. Possible indirect effects of military activities on Sonoran pronghorn, aside from direct mortality or injury, from ordnance delivery, chaff, flares, live ammunition, aircraft mishaps, interference from ground vehicles and personnel, include alteration of behavior or physiology. We conducted the study on the North and South Tactical Ranges (NTAC and STAC), BMGR, from February 1998 to June 2000. Hearing exams were conducted in Camp Verde, Arizona, the University of Arizona, and on the East Tactical Range (ETAC), BMGR. Interactions between pronghorn and military activity were restricted to 4 observation points that provided viewing areas from which pronghorn and military activity could be observed from ≤ 10 km. We systematically located pronghorn with spotting scopes and telemetry. When located, we described their behavior and military activity using scan sampling. We tested hearing using auditory brainstem responses (ABR). We could not test the hearing of Sonoran pronghorn because of their endangered status, so we contrasted hearing of pronghorn near Camp Verde, Arizona, and desert mule deer (Odocoileus hemionus eremicus) that were and were not exposed to sound pressure levels from military activity. We recorded behavior observations of Sonoran pronghorn on 172 days (44,375 observation events [i.e., 1 observation/30 second]) over 373 hours. These data were compared with 93 days of behavioral data (24,297 observation events) over 202 hours for pronghorn not regularly influenced by military aircraft. Overall, we did not detect behavioral differences (i.e., time spent bedding, standing, foraging, traveling) between males and females. Pronghorn exposed to military activity, and those that were not, bedded the same amount of time. Pronghorn at BMGR foraged less and stood and traveled more than pronghorn not exposed to military activity. These trends were the same with and without anthropogenic activity. Only 7.3% of behavioral events occurred with identifiable stimuli. Military overflights occurred 363 times (0.8%) and non-military overflights occurred 77 times ( 10 m when ground stimuli were present. Ambient noise levels ranged up to 123.1 decibels (dB). The average sound pressure level on days with military activity was 65.3 dB compared to 35.0 dB without military activity. Because we obtained hearing tests from deer and pronghorn, we were able to develop an ungulate weighting filter on the noise generated from overflights of A-10 and F-16 aircraft. Desert ungulates do not hear sound pressure levels generated from these aircraft as well as humans do (i.e., 14–19 dB lower). The military activity we examined had only marginal influence on Sonoran pronghorn. Pronghorn used the ranges shared with the military throughout the year and behavioral patterns of pronghorn were similar with and without the presence of military stimuli. Furthermore, pronghorn behavior exposed to military activity was similar to behaviors of pronghorn not exposed to regular military activity. The auditory characteristics of pronghorn were similar for those that have and have not been exposed to military activity. The population of Sonoran pronghorn in the United States continues to decline and is in serious danger of extirpation. Clearly, additional work needs to be done, but military activity as measured herein is not a limiting factor.

Sonoran pronghorn habitat use on landscapes disturbed by military activities

Abstract The Sonoran pronghorn (Antilocapra americana sonoriensis) population in the United States declined to ≤33 animals in January 2003. Low population numbers and unstable recruitment are concerns for biologists managing this subspecies. We examined habitat use by pronghorn from 1999 to 2002 on a portion of the Barry M. Goldwater Range (BMGR) used for military exercises. We overlaid locations of pronghorn (n=1,203) on 377 1-km2 blocks within the North (NTAC) and South Tactical Ranges (STAC), BMGR; we classified vegetation associations and disturbance status (e.g., airfields, targets, roads) for each block. Locations of pronghorn were distributed in proportion to vegetation associations on NTAC and STAC. Sightings of pronghorns were biased toward disturbed blocks, with 73% of locations of pronghorn occurring in proximity to mock airfields, high-explosive hills (e.g., targets for live high-explosive bombs and rockets), other targets, and roads. Disturbed landscapes on the BMGR may attract Sonoran pronghorn by creating favorable forage. Habitat manipulations simulating the effects of military disturbances on the landscape (e.g., improved forage) may improve remaining Sonoran pronghorn habitat.

Prevalence of Agglutinating Antibodies to Toxoplasma gondii and Sarcocystis neurona in Beavers (Castor canadensis) From Massachusetts

The present study examined the seroprevalence of Toxoplasma gondii and Sarcocystis neurona in a population of beavers (Castor canadensis) from Massachusetts. Sixty-two blood samples were collected during the field seasons over 3 consecutive years from different animals. Blood was collected onto filter paper and shipped to the Department of Biomedical Sciences, Virginia Tech, Blacksburg, Virginia, for parasite testing. The samples were tested at dilutions of 1:25, 1:50, and 1:100 against each parasite antigen by modified agglutination tests to determine whether antibodies to either parasite were present in the blood. Six of 62 samples (10%) were positive for T. gondii, with 2 samples having titers of 1:25 and 4 having titers of 1:50. Four of 62 samples (6%) were positive for S. neurona, with 2 samples having titers of 1:25 and 2 having titers of 1:50.

Fidelity and persistence of Ring-billed ( Larus delawarensis ) and Herring ( Larus argentatus ) gulls to wintering sites

Abstract. While the breeding ecology of gulls (Laridae) has been well studied, their movements and spatial organization during the non-breeding season is poorly understood. The seasonal movements, winter-site fidelity, and site persistence of Ring-billed (Larus delawarensis) and Herring (L. argentatus) gulls to wintering areas were studied from 2008–2012. Satellite transmitters were deployed on Ring-billed Gulls (n = 21) and Herring Gulls (n = 14). Ten Ring-billed and six Herring gulls were tracked over multiple winters and > 300 wing-tagged Ring-billed Gulls were followed to determine winter-site fidelity and persistence. Home range overlap for individuals between years ranged between 0–1.0 (95% minimum convex polygon) and 0.31–0.79 (kernel utilization distributions). Ringbilled and Herring gulls remained at local wintering sites during the non-breeding season from 20–167 days and 74–161 days, respectively. The probability of a tagged Ring-billed Gull returning to the same site in subsequent winters was high; conversely, there was a low probability of a Ring-billed Gull returning to a different site. Ring-billed and Herring gulls exhibited high winter-site fidelity, but exhibited variable site persistence during the winter season, leading to a high probability of encountering the same individuals in subsequent winters.

From the Field: Capturing beavers in box traps

Box traps have been widely used in North American wildlife research studies for live capture of terrestrial animals such as coyotes (Canis latrans) (Kamler et al. 2002, Way et al. 2002), foxes (Vulpes spp.) (White et al. 1991, Kamler et al. 2002), lynx (Lynx canadensis) (Mowat et al. 1994, Kolbe et al. 2003), and raccoons (Procyon lotof) (Gehrt and Fritzell 1996), but little is known about the efficacy of box traps to capture aquatic species such as beavers (Castor canadensis}. Beavers typically are live-captured with snares (McKinstry and Anderson 2002), suitcase-type traps like the Hancock (Hodgdon 1978) and Bailey (Buech 1983) designs, or, more recently, hand nets (Rosell and Hovde 2001). In some states, like Massachusetts, snares are illegal. Snares and Hancock and Bailey traps can be camouflaged, partially or fully submerged, and hidden from beavers. It is not known whether beavers will enter box traps, which are more difficult to conceal, on a consistent basis or whether capture would be biased to specific age or sex classes. In a review on methods of live-trapping beavers, Rosell and Kvinlaug (1998) reported that a variety of box trap designs have been used in Russia, Germany, Norway, Finland, and Sweden, primarily for nuisance beaver control, but very little quantitative information was available on the capture efficiency and sex and age composition of beavers caught with these traps. There has been no report of the use of box traps to capture beavers in North America. In a recent review of trapping techniques for mammals, Powell and Proulx (2003) do not include beaver in their list of species that can be captured with box traps. In 2001-2003, we modified and used commercially available box traps to capture beavers for a study on demography and movements of beavers across a suburban-rural gradient in 3 study areas in Massachusetts. Here we report on capture success of beavers in box traps, explain box trap designs and modifications, describe our field sets, and present costs of purchasing and modifying traps.

Habitat Use by Desert Mule Deer in a Semidesert Grassland

The desert mule deer (Odocoileus hemionus eremicus) population increased at Buenos Aires National Wildlife Refuge, southeastern Arizona, with semidesert restoration efforts for masked bobwhite quail (Colinus virginianus ridgwayi). However, use of resources by mule deer in this semidesert ecosystem is unknown. We used point transect sampling at 971 locations to describe areas used by desert mule deer relative to sex, age, and distribution on the Buenos Aires National Wildlife Refuge in 1996. We observed 219 groups of deer (50% adult females, 33% adult males, 17% juveniles and fawns, and 29% unknown age or sex) in 7 vegetation associations. We divided survey areas into quadrants (i.e., patches) to account for the mosaic of vegetation associations created by restoration efforts. There was no difference between the expected use of patch types by deer and availability in homogenous associations or in mixed patch arrangements. Because deer were more difficult to detect in dense tree cover, we analyzed habitat use with and without the dense tree association (i.e., >60% mesquite [Prosopis]) to account for this potential bias. Deer were widespread throughout the refuge. During summer and autumn mule deer used the subshrub-grass and the cactus (Opuntia) associations more than would be expected by chance alone. Current management practices on Buenos Aires National Wildlife Refuge for masked bobwhite quail appear to benefit desert mule deer.

Common Loon Incubates Rocks as Surrogates for Eggs

Abstract A nesting Gavia immer (Common Loon) was discovered incubating 2 rocks on a floating nest platform on the Quabbin reservoir in central Massachusetts for 43 days, well beyond the typical period of 28 days, before we moved in to investigate. The rocks were likely unearthed in the soil and vegetation used on the platform to create a more natural substrate for the nest. We suggest sifting through soil and vegetation to remove rocks before placing material on nest platforms.

Bombing and Sonoran Pronghorn: A Clear and Present Danger?

Abstract The United States Air Force (USAF) uses part of Sonoran pronghorn (Antilocapra americana sonoriensis) habitat for bombing exercises (i.e., Barry M. Goldwater Air Force Range [BMGR], southwest AZ, USA) that could be detrimental to the endangered subspecies. To minimize injury or death to Sonoran pronghorn, the USAF and United States Fish and Wildlife Service developed a monitoring protocol that would eliminate live ordnance delivery in the vicinity of pronghorn. From 1998 to 2003, we searched for pronghorn on or near military targets prior to ordnance delivery. If we observed pronghorn within 5 km of a target, the target was closed for ≥24 hours. We monitored bombing ranges on BMGR and closed >5,000 targets for >1,000 days due to military activity. To our knowledge, no pronghorn were killed or injured. We recommend that the monitoring program continue as long as military activity occurs in pronghorn habitat.

Interspecific interactions between badgers and red-tailed hawks in the Sonoran Desert, southwestern Arizona

Abstract Interspecific and intraspecific relationships have received much attention from ecologists and play an important role in the structure of wildlife communities, but researchers have rarely attempted to study interactions between phylogenetically unrelated organisms. We observed 6 interactions between badgers (Taxidea taxus) and red-tailed hawks (Buteo jamaicensis) between February and June 1999 on the Barry M. Goldwater Tactical Range (32°53′06″N, 112°43′24″W) near Ajo, Arizona. Each interaction lasted 5 to 20 minutes. Interactions were characterized by a red-tailed hawk following a badger as it searched for prey. On 2 occasions, red-tailed hawks apparently attempted to take prey items escaping from a badger. Badgers and red-tailed hawks feed primarily on small mammals, suggesting possible competition between the 2 species. Further research is needed to determine if badgers and red-tailed hawks in the Sonoran Desert are competing for a limiting resource or if one species (presumably the red-tailed hawk) is benefiting from the interaction without affecting the other species (badger).