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opencc-zeroJan 2021View details →

Reproductive success of the threatened San Clemente Bell's Sparrow in recovering habitats is similar to success in historical habitat

The San Clemente Bell's Sparrow Artemisiospiza belli clementeae is a federally threatened subspecies endemic to San Clemente Island, California. Previous research suggested dependence on boxthorn (Lycium californicum) as breeding habitat and nesting substrate; however, this conclusion was based on data collected when introduced feral ungulates had severely degraded the soil and vegetation cover. Since removal of the ungulates, native vegetation has gradually increased and the San Clemente Bell's Sparrows have expanded into areas where habitat had been unsuitable. To explore how Bell's Sparrows use these areas, we examined reproductive metrics associated with habitat covariates gathered at 214 nest sites used by Bell's Sparrows from 2014 ̶ 2016. We found that nest success in boxthorn habitat, previously considered an essential habitat for Bell's Sparrow nesting, was similar to success in alternative habitat types. Our findings contradict previous conclusions that Bell's Sparrows were boxthorn-dependent. We believe this previously documented relationship was likely due to the lack of available alternative nesting habitat following years of feral ungulate degradation, and Bell's Sparrows now reproduce in multiple habitat types and throughout most of San Clemente Island. Furthermore, our findings illustrate the importance of long-term monitoring and corresponding adaptive management when monitoring species in changing and recovering landscapes.The San Clemente Bell's Sparrow Artemisiospiza belli clementeae is a federally threatened subspecies endemic to San Clemente Island, California. Previous research suggested dependence on boxthorn (Lycium californicum) as breeding habitat and nesting substrate; however, this conclusion was based on data collected when introduced feral ungulates had severely degraded the soil and vegetation cover. Since removal of the ungulates, native vegetation has gradually increased and the San Clemente Bell's Sparrows have expanded into areas where habitat had been unsuitable. To explore how Bell's Sparrows use these areas, we examined reproductive metrics associated with habitat covariates gathered at 214 nest sites used by Bell's Sparrows from 2014 ̶ 2016. We found that nest success in boxthorn habitat, previously considered an essential habitat for Bell's Sparrow nesting, was similar to success in alternative habitat types. Our findings contradict previous conclusions that Bell's Sparrows were boxthorn-dependent. We believe this previously documented relationship was likely due to the lack of available alternative nesting habitat following years of feral ungulate degradation, and Bell's Sparrows now reproduce in multiple habitat types and throughout most of San Clemente Island. Furthermore, our findings illustrate the importance of long-term monitoring and corresponding adaptive management when monitoring species in changing and recovering landscapes.

opencc-zeroDec 2018View details →

Data from: Expansion of industrial plantations continues to threaten Malayan tiger habitat

Southeast Asia has some of the highest deforestation rates globally, with Malaysia being identified as a deforestation hotspot. The Malayan tiger, a critically endangered subspecies of the tiger endemic to Peninsular Malaysia, is threatened by habitat loss and fragmentation. In this study, we estimate the natural forest loss and conversion to plantations in Peninsular Malaysia and specifically in its tiger habitat between 1988 and 2012 using the Landsat data archive. We estimate a total loss of 1.35 Mha of natural forest area within Peninsular Malaysia over the entire study period, with 0.83 Mha lost within the tiger habitat. Nearly half (48%) of the natural forest loss area represents conversion to tree plantations. The annual area of new plantation establishment from natural forest conversion increased from 20 thousand ha year−1 during 1988–2000 to 34 thousand ha year−1 during 2001–2012. Large-scale industrial plantations, primarily those of oil palm, as well as recently cleared land, constitute 80% of forest converted to plantations since 1988. We conclude that industrial plantation expansion has been a persistent threat to natural forests within the Malayan tiger habitat. Expanding oil palm plantations dominate forest conversions while those for rubber are an emerging threat.

opencc-zeroDec 2017View details →

Data from: The importance of core habitat for a threatened species in changing landscapes

1. Habitat loss, fragmentation and alteration of the landscape matrix are interdependent processes, collectively responsible for most recent species extinctions. Thus, determining the extent to which these landscape processes affect animals is critical for conservation. However, researchers have often assumed that interdependent effects are independently related to animals' responses, underestimating the importance of one or several landscape processes in driving species declines. 2. We demonstrate how to disentangle the interdependent effects of habitat area, fragmentation, and edge context on population size by assessing abundance of a rapidly-declining grassland songbird species (Grasshopper Sparrow, Ammodramus savannarum) in eastern Kansas (USA). We conducted > 7,000 point-count bird surveys at > 2,000 sites over two breeding seasons, then modelled the direct, interactive, and indirect effects of landscape factors on abundance within spatial scales (200-, 400-, 800-, 1600-m radii) relevant to our focal species' dispersal behavior. 3. Sparrow abundance correlated most strongly with landscape structure within 400-m radii, increasing non-linearly with grassland area and decreasing with the proportion of grassland near cropland or woody edges. Sparrows' negative response to cropland edges was mostly an added, indirect consequence of reduced grassland area, whereas sparrows' stronger negative response to woody edges was not attributable to variation in grassland area. Fragmentation and edge context mattered most in landscapes comprising ~ 50–80% grassland. 4. Synthesis and applications. Abundance of a threatened grassland songbird was influenced more by core grassland area (a function of total grassland area, fragmentation, and edge context) than total grassland area per se. Moreover, a local extinction threshold of ~ 50% grassland indicated that small amounts of habitat were unsuitable for our focal species regardless of habitat configuration or matrix type. Local extinction thresholds in response to habitat area provide clear baseline targets for land managers; above those thresholds, configuration and the matrix can be modified to increase abundance of edge-sensitive animals. Conflicting evidence in the literature regarding the importance of fragmentation and matrix features could be partially explained by species-level traits, or methodological issues such as defining landscapes at ecologically-arbitrary spatial scales, assessing landscape quality using species richness, and ignoring interactive and indirect effects.

opencc-zeroNov 2021View details →

Habitat Selection by a Threatened Desert Amphibian

Aim. Habitat degradation and fragmentation are major drivers of amphibian declines. The loss of environmental features that allow for movement between water sources may be particularly detrimental for amphibians in arid environments. Climate changes will increase the importance of microhabitats to amphibians. Enhancing areas to facilitate movement may be a necessary conservation strategy for many animal species that depend on wetlands, including federally-threatened Chiricahua leopard frogs (Lithobates chiricahuensis). Habitat preferences of this frog species are not well understood. We sought to better understand fine-scale habitat selection, to inform conservation of Chiricahua leopard frogs. Location. We conducted our study on the Ladder Ranch, a privately-owned working bison ranch in New Mexico, USA that supports a large proportion of the remaining Chiricahua leopard frogs in the state. Methods. We attached radio transmitters to 44 frogs during summer 2014. We located each frog daily for up to 8 weeks (median = 30 days). We assessed fine-scale habitat selection by comparing characteristics at each frog location and a random location 5 meters away using conditional logistic regression. Results. Frogs preferred features that likely reduce desiccation, even after accounting for the presence of water. Frogs selected areas with more low-lying cover, especially aquatic vegetation and woody debris, a tree overstory, and a mud substrate. Main Conclusions. We recommend managing potential movement corridors for Chiricahua leopard frogs by ensuring the presence of muddy creek bottoms, woody debris, riparian overstory, low-lying ground cover, and pools. Microclimates created by these features seem especially valuable given warming temperatures and modified precipitation regimes, resulting in decreased surface water, soil moisture, and vegetation cover. Retaining or creating preferred habitat features and microclimates in areas between water sources may increase connectivity among isolated populations of Chiricahua leopard frogs and could improve persistence and recovery of other water-obligate species in arid landscapes.

opencc-zeroJan 2022View details →

Predicting habitat suitability for wild deer in relation to threatened ecological communities in south-eastern New South Wales, Australia

Context. High density deer populations can cause ecological damage, yet their distribution and impacts are poorly known across much of Australia. As a result, land managers rely on anecdotal reports to make decisions about management and control measures. Aims. We aimed to model habitat suitability for deer in the South Coast of New South Wales (NSW), Australia, to be used as a baseline for future management and identify which threatened ecological communities (TECs) in the region are at greatest current risk of being occupied by deer. Methods. We compiled 678 presence-only records of wild deer from online databases, observations made by National Parks and Wildlife Service field staff and field-based surveys. We combined these observations with eight environmental variables to model and map habitat suitability for deer across our study area using maximum entropy. Three spatial models of habitat suitability across our study area were produced: one for all deer species; and two species-specific models for fallow and sambar deer. Key results. Our models indicate that suitable habitat for deer exists throughout much of the South Coast of NSW. Of the TECs examined, Coastal Saltmarsh, Themeda Grassland, and Swamp Sclerophyll Forest had the highest proportion of area likely to be extremely suitable for deer and thus should be prioritised for protection within our study area. Conclusions. Further systematic field-based surveys are needed to improve the quality of models in this region. Implications. We recommend that areas having high habitat suitability but are not yet occupied by deer be identified as sites where deer occupancy could be prevented.

opencc-zeroApr 2022View details →

Assessing the effectiveness of a forest Habitat Conservation Plan for a threatened seabird, the marbled murrelet

Habitat Conservation Plans (HCPs) commonly facilitate habitat conservation on private land in the United States, yet the effectiveness of individual HCPs is rarely evaluated. Here, we assess the effectiveness of a high-profile HCP created by a lumber company to protect old-growth forest used for breeding by Marbled Murrelets (Brachyramphus marmoratus) on private land. We used 17 years of HCP-monitoring data to compare trends in murrelet occupancy and inland counts between private HCP areas and public reference areas over time. Based on occupancy models applied to audio-visual survey data, average occupancy was higher in public reference areas (0.85; 85% CI: 0.79-0.90) than in private HCP areas (0.46; 85% CI: 0.38-0.54). Numerically, trends in occupancy were slightly positive in public areas (λ=1.01; 85% CI: 0.94-1.08) and slightly negative in private areas (λ=0.97; 85% CI: 0.87-1.06), but confidence intervals did not preclude stable occupancy on both ownerships. Based on generalized linear mixed models applied to inland radar survey data, murrelet counts in private HCP areas (LS mean=8.7; 85% CI: 6.2-12.2) were lower than those in public reference areas (LS mean=14.8; 85% CI: 10.1-21.7), but confidence intervals overlapped. Murrelet counts declined by 12-17% annually on both ownerships over the study period based on the top model, but a closely competing interactive model suggested more rapid declines in public reference (14-20%) than in private HCP (10-15%) areas. Both models indicated that murrelet counts were negatively related to sea surface temperature, suggesting that warm ocean conditions negatively affect murrelet breeding effort. Collectively, these results suggest that while HCP habitat may be lower quality than public reference areas, the HCP has likely not exacerbated ongoing declines of murrelets in the region. This work highlights the importance of including reference areas when evaluating conservation policies.

opennotspecifiedNov 2017View details →

Distribution. Now restricted to the Channel Country of SW Queensland and the Lake Eyre Basin in NE South Australia. Descriptive notes. Head-body 95-120 mm, tail 105-160 mm, ear 23-29 mm, hindfoot 32-37 mm; weight 30-50 g. The Fawn Hopping Mouse has body form typical of hopping mice, with very long hindfeet, long tail with distal brush of longer hairs, very long ears, and large protruberant eyes. Dorsal fur is of variable color, from pale pinkish fawn to gray; ventral fur white. Unlike most other hopping mice, it has no throat pouch, but males have a glandular area of naked skin on the chest. Habitat. Occurs in low shrublands and tussock grasslands on stony ("gibber") plains and claypans. Shows marked habitat segregation from the Dusky Hopping Mouse (N. fuscus), which is closely associated with sandy substrates. Food and Feeding. The Fawn Hopping Mouse is mostly granivorous, but also eats other plant material (stems, leaves) and occasionally invertebrates. It uses succulent, salt-adapted plants around edges of claypans as a source of water. Breeding. Reproduction is probably largely opportunistic and aseasonal, with high reproductive output from near-continuous breeding after periods of high rainfall; reported littersize is 1-5, most commonly three; gestation period 38-43 days for nonlactating females. Females may mature later than other hopping mice, with reproductive maturity reached at about six months. Activity patterns. Terrestrial and nocturnal. Fawn Hopping Mice shelter during day in burrow systems that are typically simpler and shallower than those of other hopping mice. Movements, Home range and Social organization. Fawn Hopping Mice generally live singly or in small groups; typically uncommon within range, but population density may increase by an order of magnitude following periods of high rainfall. Status and Conservation. Classified as Near Threatened on The IUCN Red List. The Fawn Hopping Mouse has shown marked decline in range (estimated at greater than 50%), and presumably population size, since European settlement of Australia. This is mostlikely due to predation by the introduced house cat and Red Fox (Vulpes vulpes), and to habitat degradation associated with pastoralism. Bibliography. Brazenor (1934), Burbidge et al. (2008), Finlayson (1939), Gould (1853), Jackson & Groves (2015), Murray et al. (1999), Ogilby (1892), Thomas (1921h), Van Dyck & Strahan (2008), Waite (1898), Watts & Aslin (1981), Woinarski et al. (2014), Wood Jones (1925). in Muridae

Distribution. Now restricted to the Channel Country of SW Queensland and the Lake Eyre Basin in NE South Australia. Descriptive notes. Head-body 95-120 mm, tail 105-160 mm, ear 23-29 mm, hindfoot 32-37 mm; weight 30-50 g. The Fawn Hopping Mouse has body form typical of hopping mice, with very long hindfeet, long tail with distal brush of longer hairs, very long ears, and large protruberant eyes. Dorsal fur is of variable color, from pale pinkish fawn to gray; ventral fur white. Unlike most other hopping mice, it has no throat pouch, but males have a glandular area of naked skin on the chest. Habitat. Occurs in low shrublands and tussock grasslands on stony ("gibber") plains and claypans. Shows marked habitat segregation from the Dusky Hopping Mouse (N. fuscus), which is closely associated with sandy substrates. Food and Feeding. The Fawn Hopping Mouse is mostly granivorous, but also eats other plant material (stems, leaves) and occasionally invertebrates. It uses succulent, salt-adapted plants around edges of claypans as a source of water. Breeding. Reproduction is probably largely opportunistic and aseasonal, with high reproductive output from near-continuous breeding after periods of high rainfall; reported littersize is 1-5, most commonly three; gestation period 38-43 days for nonlactating females. Females may mature later than other hopping mice, with reproductive maturity reached at about six months. Activity patterns. Terrestrial and nocturnal. Fawn Hopping Mice shelter during day in burrow systems that are typically simpler and shallower than those of other hopping mice. Movements, Home range and Social organization. Fawn Hopping Mice generally live singly or in small groups; typically uncommon within range, but population density may increase by an order of magnitude following periods of high rainfall. Status and Conservation. Classified as Near Threatened on The IUCN Red List. The Fawn Hopping Mouse has shown marked decline in range (estimated at greater than 50%), and presumably population size, since European settlement of Australia. This is mostlikely due to predation by the introduced house cat and Red Fox (Vulpes vulpes), and to habitat degradation associated with pastoralism. Bibliography. Brazenor (1934), Burbidge et al. (2008), Finlayson (1939), Gould (1853), Jackson & Groves (2015), Murray et al. (1999), Ogilby (1892), Thomas (1921h), Van Dyck & Strahan (2008), Waite (1898), Watts & Aslin (1981), Woinarski et al. (2014), Wood Jones (1925).

Fig. 1 in Geographic Distribution and Habitat Characterization of the Threatened Delta Green Ground Beetle, Elaphrus viridis Horn, 1878 (Coleoptera: Carabidae), in the Jepson Prairie Region of Solano County, California, USA

Fig. 1. Elaphrus viridis (DGGB). a) Green and bronze adult morph, b) Green adult morph, c) Third instar larva.

Fig. 4 in Geographic Distribution and Habitat Characterization of the Threatened Delta Green Ground Beetle, Elaphrus viridis Horn, 1878 (Coleoptera: Carabidae), in the Jepson Prairie Region of Solano County, California, USA

Fig. 4. Graph of sampling plots from the four habitat types and DGGB observations based on discriminant factors DF1 and DF2.

Fig. 3 in Geographic Distribution and Habitat Characterization of the Threatened Delta Green Ground Beetle, Elaphrus viridis Horn, 1878 (Coleoptera: Carabidae), in the Jepson Prairie Region of Solano County, California, USA

Fig. 3. Examples of habitat types sampled for DGGB (see text for additional information). a) Dense valley grassland (foreground), with bare ground as a trail, leading to a playa (background), b) Playa shoreline, illustrating both bare ground and densely vegetated shoreline areas, c) Vernal pool with dense valley grassland encroaching its shoreline, d) Scattered bare ground patches in dense valley grassland.

Fig. 2 in Geographic Distribution and Habitat Characterization of the Threatened Delta Green Ground Beetle, Elaphrus viridis Horn, 1878 (Coleoptera: Carabidae), in the Jepson Prairie Region of Solano County, California, USA

Fig. 2. Map of Jepson Prairie region, with locations of 81 playas color-coded by DGGB presence or absence.

opennotspecifiedApr 2020View details →

FIGURE 3. Paepalanthus argenteus var. elatus. A, B. Habitat. C. Habit. D in Reestablishment and recircumscription of Paepalanthus elatus (Eriocaulaceae, Poales), a threatened micro-endemic species from northern Serra do Cipó, Minas Gerais, Brazil

FIGURE 3. Paepalanthus argenteus var. elatus. A, B. Habitat. C. Habit. D. Mature individual, showing inflorescences at various stages of development. E. Longitudinal section of the stem and leaf rosette, showing the yellowish caudex with marcescent leaf sheaths. F. Leaves, showing the striated indumentum on the abaxial surface and green appearance adaxially, and green scapes. G. Leaf abaxial surface, showing patent hairs and acuminate apex. H–K. Capitula in various developmental stages, from bud (H) to fruiting (K), all with long reflexed, acuminate involucral bracts; remarkable details are the capitula with staminate (I, at right, and K) and pistillate (I at left) flowers at anthesis, and the Diptera and Coleoptera flower visitors (J). (Photos: Livia Echternacht)

opennotspecifiedApr 2020View details →

FIGURE 2. Paepalanthus argenteus var. argenteus. A, B. Habitat. C–E in Reestablishment and recircumscription of Paepalanthus elatus (Eriocaulaceae, Poales), a threatened micro-endemic species from northern Serra do Cipó, Minas Gerais, Brazil

FIGURE 2. Paepalanthus argenteus var. argenteus. A, B. Habitat. C–E. Individuals representing morphological variants of the species. F–G. Rosettes of leaves showing variation in the indumentum: (F) indumentum similar to the type collection, from the population in the Fechados district neighboring P. argenteus var. elatus, (G) Individual from Diamantina. H–L. Variation in capitulum morphology from various stages of development. (Photos: Livia Echternacht)

opencc-zeroApr 2023View details →

Threatened and endangered bird species and critical habitats in US cities

Cities have classically been viewed as biologically impoverished, homogenized, and simplified systems that harbor low value for biodiversity. However, recent work has demonstrated that cities are critical ecological systems that provide important services to humanity and biodiversity. Cities can play vital roles in conserving biodiversity as well as habitats, providing system stability, and offering direct opportunities for people to engage with nature. In a rapidly changing world with biodiversity loss at an all-time high, cities have the potential to act as sanctuaries for biodiversity conservation. Here, we propose a "cities as sanctuaries" concept, which demonstrates the importance of cities for ecology and conservation, and provide the groundwork for advancing this novel field of study.

opennotspecifiedFeb 2023View details →

FIG. 3 in Breeding Population Dynamics of Threatened Crawfish Frogs Inform Targets for Habitat Management

FIG. 3. Correlation between tadpole survival and the instantaneous population growth rate (k) for 1,000 points drawn randomly from 1,000 simulations of stochastic population simulations of Nate's Pond with (left panel) and without (right panel) immigration included in the simulation model. The white line is a third order polynomial function fitted to the data, and the gray band represents the 95% confidence interval. The horizontal dashed line indicates a k of 1. The distributions of tadpole survival rates and k values are provided as marginal plots.

opennotspecifiedFeb 2023View details →

FIG. 2 in Breeding Population Dynamics of Threatened Crawfish Frogs Inform Targets for Habitat Management

FIG. 2. Percent change in the instantaneous population growth rate (k) in response to a percent change in female Crawfish Frog tadpole, juvenile, or adult survival rates for a population located in southwest Indiana, USA, between 2009–2013. Percent change in each vital rate represents the general range of that vital rate observed in this study. Change was estimated by varying the focal rate while holding all other rates constant.

opennotspecifiedFeb 2023View details →

FIG. 1 in Breeding Population Dynamics of Threatened Crawfish Frogs Inform Targets for Habitat Management

FIG. 1. (A) Post-birth, females-only, stage matrix model of Crawfish Frogs that accommodates age and state-specific transition probabilities and the ''temporary emigration'' of individuals that skip breeding or breed at other sites. (B) Projection matrix of the model used to estimate elasticities and sensitivities of vital rates. Parameters in the matrix model: embryonic survival (Se), tadpole survival (St), metamorph and juvenile survival (Sj), adult survival following the first breeding event (Sa1), adult survival following two or more breeding events (Sa2), probability that a one-year-old juvenile matures at age 2 (p), probability that a two-year-old juvenile matures at age 3 (q), the probability that a mature individual emigrates to become a non-breeding individual (c22), probability that a non-breeding individual remains a non-breeding individual (c'), and clutch size multiplied by 0.5 to represent half of all eggs developing into females (C). We assumed that all individuals mature by age 4. Individuals that emigrate to become a nonbreeding individual may either skip reproduction or breed at another site.

publicSep 2020View details →

Data from: Floral display and habitat fragmentation: effects on the reproductive success of the threatened mass-flowering Conospermum undulatum (Proteaceae)

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publicJan 2021View details →

Reproductive success of the threatened San Clemente Bell's Sparrow in recovering habitats is similar to success in historical habitat

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