Thermal characteristics of montain lion dens

We used radiotelemetry and searched with a trained hound to locate the dens of 3 recently parturient mountain lions ( Felis concolor ). These dens were located in dense riparian vegetation along the same stream in the bottom of a steep canyon. We monitored circadian temperatures of 2 dens at 1-h intervals and compared them to ambient temperatures recorded simultaneously. We found mountain lion dens to effectively moderate high ambient temperatures, but these dens failed to provide a thermal advantage at the lowest ambient temperatures recorded in this investigation. We conclude that mountain lion dens provide effective protection from thermal maxima for young, immobile kittens.     

Censusing bobcats using remote cameras

We estimated bobcat ( Lynx rufus ) density for 3 different locations in northern California using active infrared-triggered cameras. Using differences in pelage pattern as well as other physical characteristics, we identified individual bobcats from photographs, and used mark-recapture techniques to estimate population density. Camera density affected the precision of population estimates. The same population was estimated using camera densities of 0.5, 1, 2, 4, 6, and 8 cameras ? km–2. Higher camera densities resulted in more captures and recaptures of bobcats and, consequently, in more precise density estimates. Similarly, the number of photo-captures and recaptures increased with increasing study duration. Increasing the area sampled resulted in the capture of more individuals but did not increase the percentage of recaptures. While some locations captured multiple bobcat photographs (e.g., 15 at 1 station), these photos tended to be recaptures of the same individual. There were no more than 2 individuals photo-captured at any 1 camera location. Bobcat density varied among habitat types as predicted. We estimated density as 0.27 bobcats ? km –2 ( s = 0.16) overall in an area in the northern Sacramento River Valley and as 0.35 bobcats ? km –2 ( s = 0.56) in a steep and rocky canyon within the area. At a 3rd site in the Coast Range, the estimate was 0.39 bobcats ? km –2 ( s = 1.44). Bobcats were more diurnal where human activity was less common. In addition, photo-capture was significantly higher along roads and trails without an attractant than it was off-trail with an attractant.     

Age structure and growth in an isolated population of Pelodytes punctatus in northern Spain

We studied the age structure and the growth of a breeding population of parsley frogs, Pelodytes punctatus, from a pond system in northern Spain using skeletochronological methods. This population lives in an upland area with marked seasonal differences characterized by long, cold winters and dry summers. We assessed, using the mark–recapture method, the annual periodicity of bone growth marks. Only one line of arrested growth is laid down per winter, showing, in general, a well-defined histological structure. Females are larger than males with 43.31 and 36.32?mm average body length, respectively. This sexual dimorphism in body length increases with age. Males and females reach sexual maturity when they are 1 year old. The oldest males were 8 years old while the females were 2 years older. Growth curves for both sexes were constructed based on body size and the number of lines of arrested growth found in bone sections. The growth rate of males declined abruptly after the first year. Females delayed reproduction and continued to grow at a high rate for 2 years longer than males, thus reaching a higher asymptotic size.     

Survival and reproduction of translocated Eastern Wild Turkeys in a sparsely wooded landscape in northeastern South Dakota

We studied the survival and reproduction of a newly introduced population of Eastern Wild Turkeys ( Meleagris gallopavo silvestris ) during 1999 and 2000 to determine the adaptability of this subspecies to a minimally wooded (<10%) region located north of their recorded historic distribution in South Dakota. During 1999 and 2000, the South Dakota Department of Game, Fish and Parks (SDGFP) released 111 female and 25 male turkeys from Iowa and Kentucky onto a study area in northeastern South Dakota. We used radio telemetry to monitor survival and reproduction of the females for 2 years after their initial release. Annual survival for 71 females averaged 67%. Seasonal survival was lowest in fall and highest in winter. Mortality agents included avian and mammalian predators, haying equipment, automobiles, and unknown causes. Nesting rate for the 2 years averaged 93%, and renesting rate of turkeys with failed 1st-nest attempts averaged 45%. Nest success for all nests was 50%, and 62% of females attempting to nest each year were successful in at least 1 attempt. Predation was the primary cause of nest failure during both years. Overall, 72% of brooding females successfully raised ≥1 poult to 4 weeks post-hatch while individual poult survival to 4 weeks posthatch averaged 36%. Despite <10% woodland cover, Eastern Wild Turkeys appeared to thrive in a glacial escarpment topography north of their historic range in the northern plains.     

Radio transmitter attachment for chukars

Thirty-seven chukars ( Alectoris chukar ), fitted with conventional poncho-type radio transmitters, were released on Antelope Island in Utah's Great Salt Lake. Twenty-seven removed their radios, averaging three days after release. The remaining 10 died from predation (average 15 days). Twenty-two chukars with pleated and six with harness ponchos were then released. Five of the pleated ponchos were removed (average four days), and 17 resulted in mortality (average two days). All six harness poncho-equipped birds were dead the following day. A consequential laboratory study comparing various attachment methods (conventional, pleated, harness, and ""irreversible"" flange poncho vs. bellystrap and wingstrap backpack) favored the wingstrap backpack. The effectiveness of 30 conventional ponchos and 30 wingstrap backpacks was compared on game farm chukars. Twenty-nine removed their ponchos within one day. One remained attached throughout the 30-day trial. All of the wingstrap backpacks remained attached with no apparent problems.     

Diets of sympatric bobcats and coyotes during years of varying rainfall in central Arizona

We collected fecal samples (scats) of sympatric bobcats ( Lynx rufus ) and coyotes ( Canis latrans ) between 2000 and 2003 in a 53,600-ha area of the Upper Sonoran Desert in central Arizona. Our objective was to investigate composition, diversity, and overlap of diets of bobcats and coyotes in relation to varying rainfall in the Sonoran Desert of central Arizona. In general, bobcats ate more rodents than did coyotes, and coyotes ate more lagomorphs, large prey, and fruit/seeds than did bobcats. Composition of bobcat diets was independent of differences among years in annual rainfall and seasonal rainfall during summer–autumn (May–October) and winter–spring (November–April). Composition of coyote diets also was independent of drought conditions among years during summer–autumn, but coyotes ate more large prey and fewer rodents during years with winter–spring drought. Seasonally, bobcats ate more rodents than did coyotes in summer–autumn and winter–spring, whereas coyotes ate more lagomorphs than did bobcats during winter– spring, and more large prey and fruit/seeds in both seasons. Coyotes ate more large prey and lagomorphs during winter–spring, when seasonal rainfall was higher, and more fruit/seeds in summer–autumn, when seasonal rainfall was lower. Diversity of diets was consistently higher for coyotes than for bobcats, and increased for bobcats but not for coyotes during winter–spring drought and during higher seasonal rainfall in winter–spring. Overlap of diets between predators was independent of rainfall levels. We suggest that bobcats in the Sonoran Desert are more selective, specialized predators and that coyotes are more generalist, opportunistic predators. We hypothesize that, although diversity of bobcat food items and composition of coyote diets differ with varying rainfall in the Sonoran Desert, patterns of feeding strategy are independent of seasonal differences in precipitation and effects of drought, and bobcats and coyotes partition food resources independently of varying rainfall.     

Demographic characteristics of American marten populations in Jackson Hole, Wyoming

Some American marten population characteristics (numbers, density, body weights, sex and age ratios, natality, mortality-survivorship, immigration-emigration, home ranges) were studied at four sites in the southern part of the Greater Yellowstone Ecosystem, Teton County, Wyoming, in 1975-1979. Ninety-eight different martens were examined. Males (n = 25) weighed 1,111 g (± 110 SD, range 875-1,235), whereas females (n = 17) averaged 743 g (± 83 SD, range 600-900). Live-trapping showed sex ratios of 1.5M:1.0F, whereas carcasses showed 3.0M:1.0F. Of 27males that were aged, 12 (44%) were less than 1 year old and 2 were 9-10 years old. Of 10 females, 6 were less than 1 year old and 1 was 12-13 years old. The mean length of time a male was present on the major study area was 144 days (± 266 SD, range 1-1,364), and for females it was 145 days (± 45 SD, range 1-560). Home ranges for six males averaged 3.2 km 2 (± 20 SD, range 0.7-5.8) on the main study area. Some management implications are given.     

Breeding biology of Mountain Plovers ( Charadrius montanus ) in the Uinta Basin

The known Mountain Plover population breeding on the Myton Bench, Duchesne County, Utah, is small, composed roughly of 30 adults and young after each breeding season. Currently, its location is peripheral to the species main range. This shrub-steppe breeding habitat differs from the shortgrass prairie habitat with which this bird is historically associated. Between 1996 and 1998 we made observations at nesting sites located consistently in 2 concentrated areas surrounded by large tracts of similar habitat. Activity may be focused in these specific areas because of breeding-site fidelity; this behavior is common among most shorebirds and has been documented for the Mountain Plover in Colorado. Also, Mountain Plovers are social and tend to choose nest sites near others. Most nests in Utah were located within close proximity of mounds of white-tailed prairie dogs ( Cynomys leucurus ), and all were situated near roadways or oil well pads. Mountain Plovers were often observed with broods on these bare areas at night. We conclude that Mountain Plovers on the Myton Bench are distributed in clumped breeding colonies within large areas of apparently favorable habitat.     

Nest site selection by Mountain Plovers ( Charadrius montanus ) in a shrub-steppe habitat

The known Mountain Plover population breeding on the Myton Bench, Duchesne County, Utah, is small, composed roughly of 30 adults and young after each breeding season. Currently, its location is peripheral to the species main range. This shrub-steppe breeding habitat differs from the shortgrass prairie habitat with which this bird is historically associated. Between 1996 and 1998 we made observations at nesting sites located consistently in 2 concentrated areas surrounded by large tracts of similar habitat. Activity may be focused in these specific areas because of breeding-site fidelity; this behavior is common among most shorebirds and has been documented for the Mountain Plover in Colorado. Also, Mountain Plovers are social and tend to choose nest sites near others. Most nests in Utah were located within close proximity of mounds of white-tailed prairie dogs ( Cynomys leucurus ), and all were situated near roadways or oil well pads. Mountain Plovers were often observed with broods on these bare areas at night. We conclude that Mountain Plovers on the Myton Bench are distributed in clumped breeding colonies within large areas of apparently favorable habitat.     

The breeding system of an endangered pupfish ( Cyprinodon elegans )

We examined the breeding behavior of the endangered Comanche Springs pupfish ( Cyprinodon elegans ) during 3 separate breeding seasons in a pool of springwater originating in Phantom Cave, near Balmorhea State Park, Texas, in relation to behaviors reported for the species in swift-flowing canals (Itzkowitz 1969). In the quiet pool, unlike in swift water, the breeding system was characterized by 3 different male mating tactics: territorial defense, satellite positioning, and sneak spawning. Although the breeding strategies adopted by the males were conditional, mating tactics generally reflected male size. Territorial residents were the largest, satellites were medium-sized, and sneakers were the smallest adult males observed in the population. Territorial males traversed the least amount of area, defending compact territories, while satellites and sneakers covered more area in attempts to spawn. Although preferred territories in swift water centered on algal mats, territorial residents in quiet water seemed to prefer territories around large rocks. Males defending rocks had higher reproductive successes than males occupying other substrate types. The flexibility of the males' tactics was exhibited during one year of study when large males appeared to be absent from the population. During that year, medium-sized males switched from the satellite to territorial tactic, while small males remained sneakers.     

Effects of temperature on the survival and growth of age-0 least chub ( Iotichthys phlegethontis )

Larval and juvenile stages of many fishes require nursery habitats that provide optimal conditions for growth. Loss or degradation of these habitats limits recruitment, causing population and species declines. Least chub ( Iotichthys phlegethontis ), an endemic cyprinid in the Bonneville Basin, is currently restricted to a few spring complexes in Utah. This species utilizes the warm shallow spring margins as spawning and rearing habitat throughout the summer. This study was conducted to determine effects of temperature on survival and growth of age-0 least chub to understand the importance of temperature in selection of spring margins as rearing habitat. Age-0 least chub were exposed to 5 temperatures (14°C, 17°C, 21°C, 24°C, and 27°C) for 112 days. Growth rates varied significantly with temperature except at 17°C and 27°C, and growth rates were highest at 21°C ( P < 0.001). Maximum growth rate for age-0 least chub, estimated from a 2nd-order polynomial regression, would occur at 22.3°C. These thermal requirements indicate the importance of warm rearing habitats in producing strong year classes and viable populations. However, warm spring margins also enable western mosquitofish, a nonnative competitor and predator of least chub, to thrive in these spring habitats. Broad thermal limits of the least chub suggest that it could persist at cooler temperatures, which would reduce the viability of western mosquitofish populations.     

Bornean caterpillar (Lepidoptera) constructs cocoon from Vatica rassak (Dipterocarpaceae) resin containing multiple deterrent compounds

Many Lepidoptera larvae use pieces of vegetation bound with silk to construct or disguise their cocoons. Here we report the first known case of a caterpillar building its cocoon entirely out of fragments of resin, broken away from sheets of dried resin on the trunk of a tree and held together with silk. The behaviour of the larva (possibly Negritothripa sp. in the Nolidae), from the Kinabatangan Wildlife Sanctuary in Sabah, Borneo, is described. The cocoon was constructed on the trunk of Vatica rassak (Dipterocarpaceae). Analysis of resin from the cocoon, using gas chromatography-mass spectrometry, revealed a complex mixture of 260 components, dominated by sesquiterpenes and triterpenes. Many of these compounds have defensive properties, protecting the tree from herbivores and fungi. The larva appears to have evolved an elaborate and possibly unique behaviour, allowing it to harness the defensive properties of the resin to protect its pupa from predators and/or entomopathogenic fungi.     

Western balsam bark beetle, Dryocoetes confusus Swaine, flight periodicity in northern Utah

The flight periodicity of western balsam bark beetle ( Dryocoetes confusus Swaine) in Big Cottonwood Canyon, Utah, was studied during the summer months of 1992, 1993, and 1994. Contents of baited funnel traps were tallied by species up to 3 times weekly. Two main periods of flight activity were observed each year. The first and, generally, largest occurred in early summer soon after flight was initiated for the season. A 2nd period was observed in late summer, generally August. Timing of the 2 periods was influenced by unusually warm or cool weather in each study year. The 1st period had more males than females while the 2nd period had a majority of females. Except during periods of cool or wet weather, western balsam bark beetles were found to be active at least at minimal levels from June through September.     

Abundance and condition indices of coyotes on Hart Mountain National Antelope Refuge, Oregon

U.S. Fish and Wildlife Service staff at Hart Mountain National Antelope Refuge (HMNAR), southeastern Oregon, documented high pronghorn ( Antilocapra americana ) fawn mortality, subsequent low fawn recruitment, and declining pronghorn numbers from 1996 to 1999. Coyote ( Canis latrans ) predation was the primary cause, accounting for 60-85% of fawn mortalities each year, and fawns were not physiologically predisposed to predation. Therefore, we investigated certain coyote population parameters (age structure, survival, density, physiology) to evaluate how or if these factors influence coyote predation rates on pronghorn fawns. We captured 11 coyotes (5 male and 6 female) in December 1998. Age of captured animals ranged from 1.7 to 10.7 yrs (￣x = 5.0 years), and all coyotes appeared healthy upon capture. There were no known mortalities through December 1999. We estimated pre-whelping (December through February 1997-1999) density from howling surveys conducted within HMNAR to be 0.40-0.53 km -2 . Compared to other published studies, we found significant ( P ≤ 0.05) differences in selected blood parameters (e.g., blood urea nitrogen, total protein, white blood cell counts), indicating coyote nutrition may be marginal to deficient during winter at HMNAR. A high percentage of coyotes (91%) tested positive for serum-neutralizing antibodies to canine parvovirus. We judged that parasite ( Toxascaris spp., Alaria spp., Sarcocystis spp., and Isospora spp.) prevalence and intensity were not high enough to influence coyote condition. Based on our data, the coyote population at HMNAR is old aged, at a relatively high density, and stable, but their nutrition may be marginal to deficient during winter. Presently, we are unable to draw direct conclusions relating the parameters we sampled with predation rates by this unexploited coyote population.     

Spatial and temporal distribution of breeding anurans in streams in southeastern Brazil

Anuran communities were studied at eight permanent forest streams located in a preserved site in southeastern Brazil, from August 2003 to October 2004. Nineteen species were recorded in six families: Bufonidae (two), Centrolenidae (one), Cycloramphidae (one), Hylidae (12), Hylodidae (two), and Leiuperidae (one). Twelve species exhibited calling activities during the study period and 10 of these were assumed to be reproductively active. The number of species present in streams was negatively related to stream volume. The composition of anuran assemblages was related to stream volume and structural complexity of the streamside habitat. Levels of dissimilarity between anuran communities from different streams were not related to the geographical distance separating these streams. Rainfall and mean monthly temperatures were not related to anuran species diversity per month, which may be due to forested sites providing appropriate conditions for reproduction for many species year‐round and favouring anuran species with long breeding periods. The results obtained indicate that streams of varied sizes, as well as streamside habitats, should be preserved in order to maintain anuran diversity.     

Feeding by the Great Basin spadefoot toad ( Spea intermontana ) (Anura: Pelobatidae)

The present study analyzed the stomach contents of 65 Great Basin spadefoot toads, Spea intermontana (Cope), collected in an area of irrigation runoff in south central Washington State. Toads were collected by pitfall trapping. Traps were maintained for 1 year beginning in April 2002. Toads consumed at least 56 different arthropod taxa belonging to the orders Coleoptera, Diptera, Hemiptera, Hymenoptera, Lepidoptera, Neuroptera, Orthoptera, Trichoptera, Collembola, and Araneae. Ants and darkling beetles were among the most common prey. Feeding appeared to be very generalized with the toads accepting almost anything they could capture and subdue.     

Effects of burning and clipping on five bunchgrasses in eastern Oregon

Response of five perennial bunchgrasses following clipping and burning was evaluated in eastern Oregon. Burned plants were compared with clipped plants on several dates from spring to fall with respect to mortality and change in basal area. Basal area was generally reduced for one year but did not change the second year after defoliation. Treatments rarely affected yield. Burning in May was most detrimental, reducing basal area of all species. Fall clipping was least harmful, producing little or no change in basal area. Plant mortality was significant only for burned Thurber needlegrass ( Stipa thurberiana ).     

Coyote ( Canis latrans ) movements relative to cattle ( Bos taurus ) carcass areas

Use of 2 cattle carcass areas was determined for radio-collared coyotes ( Canis latrans ) in northwest Texas from January 1999 to January 2000. When 0-3 dead cattle were located at the carcass areas, resident and transient coyotes visited the carcass areas 4% and 8% of the time, respectively. However, when 30-35 dead cattle were located at 1 carcass area due to a disease epizootic, resident and transient coyotes had increased visitation rates of 19% and 63%, respectively. Resident coyotes traveled as far as 12.2 km from the center of their home ranges, suggesting that carcass areas influenced residents over a 468-km 2 area. Transient coyotes traveled from as far as 20.5 km away, suggesting that carcass areas influenced transients over a 1320-km 2 area. Our results indicate that carcass areas can influence coyotes over large areas and may concentrate both resident and transient coyotes in relatively small areas, at least for short periods.     

Breeding ecology of Long-billed Curlews at Great Salt Lake, Utah

We qualified nest site characteristics, breeding densities, and migratory chronology of Long-billed Curlews at the Great Salt Lake, Utah. The species is apparently declining in Utah, and little is known about their breeding in the eastern Great Basin Desert. This study was designed to provide wildlife biologist with the baseline data useful for their successful management. Curlews arrived in northern Utah in late March and generally departed by mid-August. Nest densities at Great Salt Lake ranged from 0.64 to 2.36 males/km 2 . The habitat at curlew nest sites consisted of significantly shorter vegetation than nearby random locations ( ˉx = 5.7 versus 9.0 cm, respectively; P < .01). Nests tended to be located in small patches of vegetation near barren ground. Maintenance of relatively short vegetation appears to be important in managing curlew habitat. In addition, only 2 of 10 nests we monitored in 1992 were successful, with most lost to mammalian predators. Further research is needed to determine impact of mammalian predators on curlew populations.     

Age and population structure of Joshua trees ( Yucca brevifolia ) in the northwestern Mojave Desert

Many desert perennials are long-lived, but there are few data on ages or population structures of desert plants. We used 2 methods to estimate ages of a population of Yucca brevifolia (Joshua tree) in southwestern Utah from a 14-year census of plant sizes. Plant height at the 1st census ranged from 0.08 m to 6.0 m, and trees grew in height at a mean rate of 3.75 cm ? yr -1 . Plants also increased slowly in basal diameter (0.142 cm ? yr -1 ) and branch length (0.024 m ? yr -1 ), but basal diameter varied greatly from year to year, with many plants decreasing in diameter between sequential censuses. Forms of a nonlinear growth equation (the Richards function) did not fit the data on growth in height, but a simple linear relationship fit the data well. Using height as a linear predictor of age, we estimated that ages of a sample of 69 Joshua trees ranged from 300 years old, with 75% of the trees between 20 and 100 years and 11% over 150 years old. These data support the assumption that Joshua trees are indeed long-lived.