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The United States Fish and Wildlife Service (USFWS) uses a Species Status Assessment (SSA) framework to inform Endangered Species Act (ESA) policy decisions. A major challenge for development of SSAs includes inconsistent or incomplete monitoring throughout a species' range, which can result from inadequate time and funding for data collection prior to final rulings. In 2014, the USFWS initiated an SSA for the Sprague's pipit (Anthus spragueii; hereafter pipit), a migratory songbird scheduled for consideration as Threatened or Endangered in fall 2015. At the time, researchers had no field data to identify the spatial distribution of habitat across the geographic extent of the pipit's wintering grounds or to forecast the species' response to probable future scenarios of environmental conditions or conservation efforts during winter. In addition, the timing of the ESA decision precluded range-wide surveys on the pipit's wintering grounds. We present an SSA case study to demonstrate how citizen science and remotely sensed data could be integrated to help inform time-sensitive policy decisions for species of conservation concern. We developed three independent estimates of potential pipit habitat, and we assumed that spatial congruence among models provided increased evidence of habitat likely to support our focal species. We do not suggest that our approach replace more robust analyses, but rather illustrate an alternative strategy to obtain baseline information for SSAs and other policy decisions when data and time are lacking.

North American porcupines (Erethizon dorsatum) have expanded their range into central Texas and are now frequent users of caves as den sites. What remains unknown is how caves affect their home range, and their local habitat preferences. This information is important for management decisions on Joint Base San Antonio – Camp Bullis where novel and abundant porcupine scat in caves could jeopardize federally endangered cave-obligate arthropods by allowing for the invasion of less specialized terrestrial species. To better understand porcupine home range and habitat use at Camp Bullis, we trapped four porcupines at cave entrances and fitted them with GPS collars. The 95% home range averaged 71.3 ha for females and measured 420.6 ha for the male. The 50% core habitat averaged 55.4 ha for females and measured 7.4 ha for the male. Porcupines typically stayed near the den-cave trap site except when visiting more diverse mixed forest patches. At the landscape and point levels, individuals selected for forested cover and avoided open areas. At the home range level, individuals selected for bare ground and roads, which were likely used to get from the cave den site to feed at mixed forest patches. Typically solitary, individuals in this study tolerated sharing a cave. Because of the small sample size and single sampling location, this study represents a pilot study and additional research is needed to establish concrete conclusions. Should cave managers need to limit the cave use by porcupines, a cave gate, exclosure, or reduction of forested cover would make caves less desirable.

Sylvilagus palustris hefneri (Lower Keys Marsh Rabbit [LKMR]) is an endangered subspecies of marsh rabbit found only in the Lower Florida Keys. In September 2017, Hurricane Irma was measured as a Category 4 storm when it passed through the center of the LKMR range causing significant damage to human infrastructure and natural habitats. To assess the impact of Hurricane Irma to LKMR and its habitat, we compared pre- and post-hurricane monitoring data. Overall, 82% of LKMR habitat patches were abandoned, the average number of pellets per sampling plot decreased 94%, and average patch pellet density decreased by 84% following Hurricane Irma. Generally, pellets were found in plots with greater open cover, an intermediate amount of herbaceous and woody cover, and areas with more standing water post-Hurricane Irma. We also observed a slight decrease in signs of Procyon lotor (Raccoon) and Didelphis virginiana (Virginia Opossum). The decrease in rabbit pellets detected after Hurricane Irma is likely attributed to both direct mortality from the storm and flooding, as well as indirect mortality from the loss of critical, salt-sensitive herbaceous cover. Because climate-change models suggest increases in future flooding and hurricane frequency, we recommend that wildlife managers continue to closely monitor the recovery of LKMR populations and their habitat to determine if more active management actions (e.g., habitat remediation, translocations, or captive breeding) are necessary.

Pituophis ruthveni (Louisiana Pinesnake) is one of the rarest snakes in the United States. Efforts to refine existing habitat models that help locate relictual populations and identify potential reintroduction sites are needed. To validate these models, more efficient methods of detection for this rare species must also be developed. Here we expand recent habitat suitability models based on edaphic factors to include mature Pinus (pine) stands that have not been cut for at least 30 years and likely have vegetation structure with the potential to support the species. Our model identified a total of 1652 patches comprising 180,050 ha of potentially suitable habitat, but only 16 (1%) of these patches were more than 1000 ha and considered worthy of conservation attention as potential reintroduction sites. We also visited potentially suitable habitat, as determined by our model, and used camera traps to survey for relictual populations at 7 areas in Texas. We observed 518 snakes of 18 species in 8,388,078 images taken from April to October 2016, but no Louisiana Pinesnakes were detected. The patchiness of the habitat model and failure to detect Louisiana Pinesnakes corroborate independent conclusions that most populations of the species are small, isolated, probably in decline, and possibly extirpated. In the context of this extreme rarity, we believe this study will help manage limited conservation resources by narrowing the search areas for relictual populations, providing a more cost-effective method of surveying those areas, and identifying the best sites for future reintroduction efforts.

Freshwater resources in arid and semi-arid regions are in extreme demand, which creates conflicts between needs of humans and aquatic ecosystems. The Rio Grande basin in the southwestern United States and northern Mexico exemplifies this issue, as much of its aquatic biodiversity is in peril as a result of human activities. Unionid mussels have been disproportionately impacted, though the specific factors responsible for their decline remain largely unknown. This is problematic because the Rio Grande basin harbors one federally endangered unionid mussel (Popenaias popeii, Texas Hornshell) plus two other mussel species (Potamilus metnecktayi, Salina Mucket; and Truncilla cognata, Mexican Fawnsfoot), which are also being considered for listing under the U.S. Endangered Species Act. To date, surveys for these species have not corrected for variability in detection so current range estimates may be inaccurate. Using single occupancy-modeling to estimate detection and occupancy at 115 sites along ~800 river kilometers of the Rio Grande in Texas, we found that detection probabilities were relatively high, indicating that our survey design was efficient. In contrast, the estimated occupancy was low, indicating that our focal species were likely rare within the Rio Grande drainage. In general, the predicted occupancy of our focal species was low throughout their respective ranges, indicating possible range declines. A comparison of currently occupied ranges to presumptive ranges underscores this point. The best-approximating models indicated that occupancy was influenced by habitat, water quantity and quality, and proximity to large-scale human activities, such as dams and major urban centers. We also discuss a series of conservation options that may not only improve the long-term prognosis of our focal species but also other aquatic taxa.

We studied Greater Roadrunner (Geococcyx californianus) habitat use during spring and summer 2011 on the Rolling Plains Quail Research Ranch in the Red Rolling Plains of west Texas. We captured 9 roadrunners (1 male, 8 females) and fitted each with a 10-g backpack-style radio-transmitter. We relocated roadrunners 2–4 times per week from February to August. Roadrunners used a mean minimum convex polygon home range of 43.0 ha, a 50% core range of 11.9 ha, and 33% overlap between adjacent home ranges. Home ranges were approximately half the size of those reported in a recent study of roadrunners in north Texas. Habitat selection ratios showed that roadrunners selected for ridge and grassland vegetation types and avoided bare ground and flatland vegetation types at both first- and second- but not third-order levels of selection. Similar results were documented for roadrunners in north Texas.

We studied Greater Roadrunners' (Geococcyx californianus) habitat use during spring and summer of 2011 in the Red Rolling Plains of west Texas. We captured 10 roadrunners (one male and nine females) and fitted each with a 10-g backpack style radio-transmitter. Roadrunners were relocated 2–4 times per week from February–August. We used these data to build a logistic regression model to better understand the vegetative and topographic features important to roadrunners during the nesting season. The initial data set consisted of 30 random and 30 used locations. The best model showed both percent rock and percent litter to be higher at used locations and correctly classified 88% of the sites. Evaluation of the model with an additional 30 random and 30 used locations maintained significance of both the model and variables and correctly classified 83% of sites. Both variables were associated with the location's mesa ridge slopes. Litter dominated locations under shrubs on the ridge tops and slopes and ...

Degradation of coastal systems has led to increased impacts from hurricanes and storm surges and is of concern for coastal endemics species. Understanding the influence of disturbance on coastal populations like the endangered Lower Keys marsh rabbit (Sylvilagus palustris hefneri) is important to understanding long-term dynamics and for recovery planning. We evaluated the effect of disturbance on the rabbits by determining which patch, habitat, and landscape characteristics influenced habitat use following Hurricane Wilma. We determined patch-level occurrence 6–9 months prior to Hurricane Wilma, within 6 months following the hurricane, and 2 years after the storm to quantify rates of patch abandonment and recurrence. We observed high patch abandonment (37.5% of used patches) 6 months after Hurricane Wilma and low rates of recurrence (38.1% of abandoned patches) 2 years after the storm, an indication that this storm further threatened marsh rabbit viability. We found the proportion of salt-tolerant (e.g., mangroves and scrub mangroves) and salt-intolerant (e.g., freshwater wetlands) vegetation within LKMR patches were negatively and positively correlated with probability of patch abandonment, respectively. We found patch size and the number of used patches surrounding abandoned patches were positively correlated with probability of recurrence. We suggest habitat use following this hurricane was driven by the differential response of non-primary habitats to saline overwash and habitat loss from past development that reduced the size and number of local populations. Our findings demonstrate habitat use studies should be conducted following disturbance and should incorporate on-going effects of development and climate change.

Conservation areas in tropical forests protect the most diverse and threatened ecosystems on the planet. In the Amazon, ungulates are important determinants of forest structure and plant diversity, as well as being a resource for rural communities. Using occupancy-based methods, we estimated the occurrence of white-lipped peccary Tayassu pecari, collared peccary Pecari tajacu, lowland tapir Tapirus terrestris and red brocket deer Mazama americana in and around protected areas reserve in Tambopata, Peru, to evaluate how different management designation, anthropogenic influences and habitat type influenced the occurrence of each species. We used a combination of track surveys (n=258) and camera surveys (n=256) to estimate ungulate presence at 55 sites in a national reserve, a native community and adjacent buffer areas from May 2008 to March 2009. We found that prediction of the occurrence of white-lipped peccary, lowland tapir and red brocket deer was best accomplished using travel time from the nearest city (a measure of an area's accessibility). The occurrence of ungulates differed little between buffer and reserves, but community lands managed by indigenous peoples showed reduced probabilities of ungulate occurrence. Our results indicate that passive protection afforded by inaccessibility might be an effective management strategy for this region; however, we doubt that this is tenable as a long-term solution.

The Lower Keys marsh rabbit (LKMR, Sylvilagus palustris hefneri), a marsh rabbit subspecies endemic to the Lower Keys, Florida was protected in 1990, however, populations continue to decline despite recovery efforts. We hypothesized on-going habitat loss and fragmentation due to succession and hardwood encroachment has lead to increased edge, reduced habitat quality, and increased activity by native raccoons (Procyon lotor). These factors reduce the suitability of patches in a later successional state, thus threatening LKMR recovery and metapopulation persistence. We surveyed 150 LKMR patches in 2008, tallying adult and juvenile rabbit pellets, estimating measures of habitat succession and quality (woody and herbaceous ground cover, distribution of herbaceous species) and recording raccoon activity (number of raccoon signs). We calculated patch edge (patch shape index) using ArcGIS. We evaluated the relationship between patch and habitat attributes and LKMR using regression analysis and model selection. We found both adult and juvenile LKMR pellet counts were lower in patches with higher shape indices and higher in patches with greater occurrence of bunchgrasses and forbs. We also found adult LKMR pellet counts were lower in patches with higher raccoon activity. Our results suggest patch edge, habitat succession and quality, and raccoons pose a threat to the persistence and recovery of LKMR populations. Recovery efforts should focus on reducing these trends through habitat management and raccoon removal implemented in carefully controlled experiments with proper monitoring. Measures of patch and habitat attributes important to LKMR should be incorporated into long-term metapopulation monitoring and used to evaluate recovery actions. Published by Elsevier Ltd.

The expansion of urban areas into native habitat can have profound effects on avian populations and communities, yet little is known regarding the effects of urban features on avian reproductive success. The objective of this study was to examine the reproduction of an urban-enhanced species, the mourning dove, to determine how tree and urban landscape features affect nest-site selection and nest success. Mourning dove nests were located by systematically searching potential nest sites on a weekly basis from late-March through mid-September in 2003 and 2004. A total of 1,288 mourning dove nests were located and monitored on the Texas A&M University Campus. Of these nests, 337 (26.6%) were successful (fledged, ≥1). An equal number of potential nest sites were randomly generated in ArcGIS and assigned to non-nest trees to evaluate habitat variables associated with nest-site selection. Mourning dove nests were located in trees with a larger canopy diameter and diameter at breast height (DBH) than the computer generated potential nests and nest trees were located closer to roads and farther from buildings than non-nest trees. Within the study area, nest success was predominately influenced by the proximity of urban features with successful nests being located closer to roads and farther from buildings than unsuccessful nests.

We used radiotelemetry to locate daytime forms of endangered Lower Keys marsh rabbits (LKMRs; Sylvilagus palustris hefneri) throughout their range so we could determine habitat characteristics of diurnal cover. We typically found forms (n = 1,298) of 36 rabbits in brackish wetlands in patches of saltmarsh or buttonwoods. In freshwater wetlands, forms (n = 54) were located most often in patches of freshwater hardwoods embedded in or adjacent to freshwater marshes. Forms (n = 942) in brackish wetlands were characterized by thick groundcover (>75%), whereas those (n = 42) in freshwater wetlands had both thick groundcover and canopy vegetation. The mean minimum convex polygon around forms of 15 rabbits was 1.4 ha (SD = 1.7), with smaller ranges characterized by thick bunchgrasses or clump-forming sedges. To increase the amount of annual space usable by LKMRs, managers should provide more saltmarsh habitat interspersed with buttonwoods and enhance ground cover in existing habitat.

Many rangelands in the southwestern United States provide quality habitat for Northern Bobwhites (Colinus virginianus). These same habitats are frequently managed for livestock production and thus are subjected to various brush management practices that are meant to enhance forage production. Bobwhites rely on woody cover for food, thermal and loafing cover, and protection from avian predators. Implementing brush management practices that reflect bobwhite requirements is important for managing usable space and viable populations. We described the struc- tural vegetative characteristics associated with bobwhite locations and random locations on native rangelands in the upper Rolling Plains of Texas that are dominated by honey mesquite (Prosopis glandulosa) and managed with aerial her- bicide and prescribed fire. We also used binary logistic regression to model habitat selection; the initial model was built using 67% of the data (n = 179 used-random paired points) and then validated using the remaining 33% of the data (n = 88 used-random paired points). Locations used by bobwhites had significantly larger mean values of percent brush canopy cover, visual obstruction, and angle of obstruction than did random locations; random locations had a greater mean value of percent bare ground than locations used by bobwhites. The resulting logistic regression model contained only the angle of obstruction; the model had an 80% probability of correctly classifying used and random locations based on the area under the receiver operating curve (ROC). The model maintained a high classification probability when applied to the smaller validation data set, with an area under the ROC of 0.78.

Surface-mined land reclamation creates grass and shrub lands that provide important wildlife habitat, particularly for disturbance-dependent birds. Declines in disturbance-dependent birds have been observed for 30 years, emphasizing the importance of proper reclamation strategies. Understanding the influence of spatial factors on nesting ecology of avian populations can improve restoration strategies on reclaimed mines. We evaluated the influence of spatial factors on nest site selection, nest success, and nest parasitism of dickcissels (Spiza americana) on two sites reclaimed as wildlife habitat on the Big Brown Mine, Freestone County, Texas, in 2002–2003. We found 119 nests, 14 of which were parasitized by the brown-headed cowbird (Molothrus ater). Dickcissels were more likely to select nest sites farther from riparian areas and closer to brush-encroached areas. Nest success was not clearly explained by one or few variables. Parasitism was more likely to occur near riparian areas and roads. For these reasons, we suggest the establishment of larger wildlife habitat blocks, which would provide more field-interior habitat for dickcissels and similar species.

Status assessment of endangered Florida Key deer (Odocoileus virginianus clavium) is currently limited by a paucity of information regarding population estimates for outer islands, which collectively comprise approximately 70% of potential habitat within the Key deer range. Practical limitations and financial considerations render traditional survey techniques impractical for application on remote outer islands. Our objective was to evaluate the utility of infrared-triggered cameras to estimate Key deer abundance on outer islands. We used digital infrared-triggered cameras and mark–resight methods to estimate Key deer abundance on 20 outer islands. Abundance estimates for primary subpopulations ranged from 15 to 16 for Howe Key, 5 to 10 for Knockemdown complex, and 13 to 17 for Little Pine Key. Other island complexes such as Ramrod Key, Water Key, and Annette complex maintain only small subpopulations (i.e., ≤5 individuals) and other previously inhabited island complexes (e.g., Johnson complex an...

Tree squirrels are one of the most familiar mammals found in urban areas and are considered both desirable around homes and, conversely, a pest. We examined fox squirrel (Sciurus niger) habitat use in inner city and suburban areas using radiotelemetry. We estimated habitat selection ratios at differing scales by season and fox squirrel activity. Telemetry data suggests that during periods of inactivity radiocollared fox squirrels (n = 82) selected 1) areas with greater tree canopy, 2) live oaks (Quercus fusiromis and Q. virginiana), and 3) trees with larger diameters and canopies. When inactive during the winter and spring, fox squirrels also preferred, within their core areas, to use the inside of buildings, and during periods of activity in the autumn and spring, fox squirrels preferred grassy areas. During periods of activity, fox squirrels avoided using pavement but did not exclude it from their core-area movements. Fox squirrels' ability to use buildings and to tolerate pavement in core-area...

The Lower Keys marsh rabbit (LKMR; Sylvilagus palustris hefneri) is endemic to the Lower Keys of Florida and exists as a metapopulation in patches of salt-marsh–buttonwood transition zone, freshwater wetlands, and coastal beach berm vegetation (Forys and Humphrey 1996). Local LKMR populations interact through dispersing individuals, and patches undergo periodic local extinctions and recolonization (Forys and Humphrey 1999a). Much of the LKMR’s habitat has been lost or fragmented by human development over the past several decades, prompting the United States Fish and Wildlife Service (USFWS) to list the subspecies as endangered in 1990 (USFWS 1990). Knowledge of the distribution of occupied and potential LKMR habitat patches is critical to the design of recovery strategies for the subspecies. Historically, LKMRs occupied most, if not all, larger islands from Big Pine Key to Boca Chica Key, and may have occurred on Key West as well (DePourtales 1877, Layne 1974, Howe 1988, Lazell 1989; D. Stevenson, Felix Environmental Services, personal communication; Fig. 1). Although rapid habitat loss occurred in the 1970s and 1980s (USFWS 1997), little information is available on the LKMR’s distribution prior to 1988. The oldest known written records are anonymous notes dated 1968–1987 written on blue line photographs discovered at the National Key Deer Refuge in 2003. These records documented presence of LKMRs at 20 sites on Big Pine Key. Howe (1988) conducted the first published survey of the LKMR metapopulation by surveying 13 patches noted by J. Lazell (The Conservation Agency, unpublished data) and 3 additional patches. He reported that rabbits were absent from 4 of these patches, no longer occurred on Cudjoe Key, and were threatened by human activities in remaining patches. Forys (1995) completed a more comprehensive survey from 1991 through 1993. She identified 59 patches of occupied and potential (i.e., unoccupied, but apparently suitable) LKMR habitat. This survey included all but 2 of the patches noted by Howe (1988). LKMRs consistently occupied 19 of these patches over the course of her study, occupied 23 other patches in 1 survey, and did not occupy 17 patches. In 1995, Forys et al. (1996) discovered an additional 19 and 47 occupied and potential patches, respectively. Forys (1995) and Forys et al. (1996) found no extant populations between Big Pine and Sugarloaf keys. Based on these surveys and demographic data collected by Forys (1995), a population viability analysis (PVA) model suggested the metapopulation had a 100% probability of extinction in the next 50 years (Forys and Humphrey 1999b). Researchers have not formally surveyed the range-wide status and distribution of the LKMR since the mid-1990s. Managers charged with the recovery of this species need current data. Therefore, we surveyed potential LKMR habitat throughout the Lower Keys from 2001 through 2005. Specifically, our objectives were 1) to update the distribution and occupancy status of LKMR habitat patches, 2) to document patterns in patch occupancy from 2001 through 2005, and 3) to draw comparisons to previous formal and informal surveys.

We radio-collared and tracked 16 (10 female, 6 male) Neotoma floridana smalli (Key Largo woodrats) from March–November 2002 and recorded a total of 631 locations. The average monthly ranges of individual male and female woodrats were 4756 (95% CI = 2376–7136) m2 and 2051 (95% CI = 1091–3011) m2, respectively. We found male and female ranges to be significantly different (P = 0.032). Female ranges varied with season (P = 0.032), while male ranges did not (P = 0.567). Spring (P = 0.033) and summer (P = 0.019) ranges were significantly different between sexes. At two spatial scales, Key Largo woodrats showed a preference for young habitat with selection ratios of 6.3 and 6.7. Six female ranges overlapped an average of 49% and 2 males overlapped an average of 8%. No woodrats were recorded crossing a major road. Study results suggest that N. f. smalli prefer early succession hammock, male woodrats should be introduced separately, and a major road is a barrier to woodrat movements.

The endangered Lower Keys marsh rabbit (LKMR; Sylvilagus palustris hefneri) exists as a metapopulation in patches of wetland habitat in the Lower Florida Keys, USA. The recovery plan for the LKMR recommends reintroducing rabbits to unoccupied but potentially suitable patches. The effectiveness of such reintroductions has not been evaluated. We translocated 12 and 7 rabbits fitted with radiotransmitters to patches of apparently suitable vegetation on Little Pine and Water Key during 2002 and 2004, respectively. Our radiotelemetry-based study monitored survival, site fidelity, and reproduction. We observed high survival (81% of known-fate rabbits on Little Pine and 100% on Water Key), fidelity to release sites (mean distance from release sites

The aim of the present study was to estimate changes in plant species composition in sev- eral forest communities caused by changes in endangered Key deer (Odocoileus virginianus clavium) densities in the National Key Deer Refuge in the lower Florida Keys. Baseline vegetation quadrats from a 1990 study were resampled in 2002 (the present study) in buttonwood transition, hardwood hammock, and mangrove wetland communities (all deer habitat) on 12 islands with low, medium, and high Key deer densities. On islands with high Key deer densities (>17 deer km -2 ), the relative densities of pre- ferred plant species 1.2 m tall (midstory/canopy) also significantly decreased in hammock on islands with high deer density, suggesting that heavy browsing is deterring plant growth/recruitment, thus already affecting regeneration of certain plant species into the midstory/canopy tiers. Plant species richness did not vary significantly between 1990 and 2002 for islands with high deer densities, but tended to increase slightly on islands with low deer density in but- tonwood and hammock communities. Evidence from this study suggests that high densities of Key deer influence plant species composition on certain islands. We suggest that management plans for Key deer should incorporate both species protection components and population control techniques dependent on deer density-island associations.

Over the last two decades, declines in trap success, stick-nest density and population density estimates have fueled concerns that the federally endangered Key Largo woodrat (KLWR, Neotoma floridana smalli) population is declining. Information on the current population status and habitat selection of KLWR is needed in the recovery of this population. We trapped on 60 (1-ha) randomly-placed grids (20 grids in each of three hardwood hammock age-classes). Grids were trapped from March–September 2002 and April–August 2004. Population estimates for the two trapping periods were 106 (95% ci 30–182) and 40 (95% ci 5–104) individuals, respectively. Greater than 80% of all KLWRs captures occurred in the young hammock age-classes (disturbed after 1971). Young hammocks were characterized by a more open canopy, smaller overstory trees, fewer logs, greater dispersion of overstory trees and a different species composition than old and medium age hammocks (P < 0.024). Contrary to previous research, KLWRs were f...

Drift fences, often in conjunction with pitfall or funnel traps, commonly are used to capture amphibians and reptiles (Gibbons and Semlitsch 1981, Corn 1994), small mammals (Kirkland and Sheppard 1994), and fledgling birds (Nettleship 1969). Gibbons and Semlitsch (1981) noted the incidental capture of eastern cottontails (Sylvilagus floridanus) using drift fences with pitfall traps. However, with the exception of Ludeman (1954), who suggested drift fences as a means to prevent porcupines (Erethizon spp.) from damaging trees, we are unaware of drift fences being used for the purpose of capturing of medium-sized mammals. Listed as federally endangered in 1990, the Lower Keys marsh rabbit (hereafter marsh rabbit; S. palustris hefneri) exists as a metapopulation in 102 patches of wetland habitat in Florida's Lower Keys (United States Fish and Wildlife Service 1990, Forys and Humphrey 1996, Faulhaber 2003). In areas with thick grasses (e.g., gulf cord grass [Spartina spartinae] and saltmeadow cordgrass [Spartina patens]), the conventional method for trapping marsh rabbits consists of placing nonbaited 2-door live traps in tunnels and corridors through the vegetation (Forys 1995, Faulhaber 2003). However, habitats with low or sparse herbaceous growth, such as saltmarshes dominated by seashore dropseed (Sporobolus virginicus) and some areas within sawgrass (Cladium jamaicense) marshes, did not provide the vegetation structure required for this method. Trapping alternatives included use of baits or scent (e.g., domestic rabbit urine); however, Forys (1995) and Faulhaber (2003) were unable to find a suitable bait to lure marsh rabbits into traps, and some baits posed the additional problem of attracting raccoons (Procyon lotor). Domestic rabbit urine could not be used as it may have posed a disease problem to this endangered species. Here we describe the use of drift fences in conjunction with 2-door live traps to capture marsh rabbits in habitats where conventional trapping methods were unsuccessful or unfeasible.

The relationship between population density and range size has long been debated. While many studies have documented varying responses in range size to changes in pop- ulation densities, most have been the result of experimental manipulation. We examined the effects of long-term density changes in Florida Key deer (Odocoileus virginianus clav- ium) on range and core-area sizes. We radiocollared Key deer as part of 2 separate research projects conducted December 1968-June 1972, and January 1998-December 2001. We used a total of 96 (females, n = 62; males, n = 34) and 163 (females, n = 88; males, n=75) radiocollared Key deer to calculate annual and seasonal ranges and core areas, respectively. Season and age were not important factors in describing ranges and core areas of Key deer, while sex and period (early vs. current study) were important. On average, male annual ranges (x - = 221 ha, current; x - = 388 ha, early) were greater than female annual ranges (x - =42 ha, current; x - =101 ha, early), which might explain higher male mortality due to roadkills. Early ranges and core areas were greater (≈2x) than cur- rent ranges and core areas. We suggest that increased deer densities may have resulted in a decrease in Key deer ranges. Other factors influencing changes in Key deer ranges included increased habitat quality and Key deer domestication over the last 30 years.

Urban development in the Florida Keys, USA, mandates an understanding of how habitat requirements for Florida Key deer (Odocoileus virginianus clavium) interact with vegetation changes caused by development. Our study objectives were to (1) determine Key deer habitat use at different spatial scales, (2) evaluate vegetation changes and identify vegetation types most threatened by development, and (3) provide guidelines to direct land acquisition programs in the future. We identified 6 vegetation types: pineland, hammock, developed, freshwater marsh, buttonwood, and mangrove. Key deer (n = 180; 84 F, 96 M) preferred upland vegetation types (>1 m above mean sea level; pineland, hammock, developed) and avoided tidal or lower-elevation areas (

Assuming that a finite biosphere can support infinite development seems logically inde- fensible, yet the concept of sustainable development has become a dominant conserva- tion paradigm. The story of the endangered Florida Key deer (Odocoileus virginianus clavium) appears to support the legitimacy of sustainable development because Key deer numbers have increased 240% since 1970 while at the same time human numbers in their habitat increased nearly 10-fold. Because fawn mortality is considered the primary density-dependent factor regulating cervid populations as they approach K-carrying capacity, we hypothesized that changes in fawn demographics could elucidate the falla- cy in assuming that development was sustainable on Big Pine Key. We determined and compared survival and range sizes for Key deer fawns between 1968-1972 (early urban development) and 1998-2002 (post-urban development). Fawn ranges (95% probability area, 149 to 33 ha) and core areas (50% probability area, 25 to 6 ha) decreased during this period of development while 6-month survival increased (0.47 to 0.96). All fawn mortality was due to anthropogenic causes; the positive relationship between fawn sur- vival and development may be a function of isolating fawns from anthropogenic mortal- ity. If this is true, the relationship is not sustainable because as ranges continue to shrink, they eventually will lack sufficient resources to support a fawn.

Obtaining reliable population estimates is imperative in managing wildlife populations, particularly when attempting to implement nuisance control measures. Free-roaming cats ( Felis catus ) impact wildlife worldwide through predation, competition and disease transmission. Ideally, measures of controlling free-roaming cat populations should be evaluated a priori, which requires obtaining population estimates for use in population control programs (e.g., euthanasia, trap/treat/neuter/release). We compared mark-resight and distance sampling abundance estimates of free-roaming cats in an urban landscape, where limited public access to habitat frequently hinders the use of probabilistic sampling designs and associated sampling methodologies. We marked a subset of free-roaming cats (n = 52) with radio-collars in Caldwell, Texas to aid in obtaining our estimates. From road surveys (n = 20) conducted in August 2005, we found mark-resight estimates (N = 744, 95% CI 518-1,135) were significantly different (p = 0.008) to distance sampling estimates (N = 296, 95% CI 262-333). Study results suggest that distance sampling provides wildlife managers a viable alternative for estimating free-roaming cat populations in urban areas where minimal cost and training influence policy decisions regarding the implementation of monitoring and population control measures.

Human-induced global climate change presents a unique and difficult challenge to the conservation of biodiversity. Despite increasing attention on global climate change, few studies have assessed the projected impacts of sea-level rise to threatened and endangered species. Therefore, we estimated the impacts of rising sea levels on the endangered Lower Keys marsh rabbit (Sylvilagus palustris hefneri) across its geographic distribution under scenarios of current conditions, low (0.3-m), medium (0.6-m), and high (0.9-m) sea-level rise. We also investigated the impacts of allowing vegetation to migrate upslope and not allowing migration and of two land-use planning decisions (protection and abandonment of human-dominated areas). Not surprisingly, under all simulations we found a general trend of decreasing total potential LKMR habitat with increasing sea-level rise. Not allowing migration and protecting human-dominated areas both tended to decrease potential LKMR habitat compared with allowing migration and abandoning human-dominated areas. In conclusion, conservation strategies at multiple scales need to be implemented in order to reduce the impact of global climate change on biodiversity and endangered species. At the regional level, managers must consider land-use planning needs that take into account the needs of both humans and biodiversity. Finally, at the local scale those agencies that are in charge of endangered species conservation and ecosystem management need to rethink static approaches to conservation or else stand by and watch ecosystems degrade and species go extinct. This can be accomplished by bioclimatic reserve systems where climatically underrepresented areas are included in conservation planning along with the standard concerns of threat, opportunity, connectivity, and viability.

Pinnated grouse (prairie-chickens, Tympanuchus spp.) are declining throughout their range. Historically, there were 3 pinnated grouse in Texas: Attwater's prairie-chicken (T. cupido attwateri), greater prairie-chicken (T. c. pinnatus), and lesser prairie-chicken (T. pallidicinctus). Factors such as habitat quality and genetic isolation that can affect survival may limit a population, but evidence indicates that usable space (habitat quantity) is the factor responsible for the long-term decline of pinnated grouse in both Texas and North America in general. There is a need to restore former pinnated grouse habitat because current habitat space will not save pinnated grouse in Texas from extinction over the long term. Programs within the current Farm Bill offer an opportunity for restoring these former habitats. Research is needed to determine the most effective and economical way to restore former habitat.