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Each year in the United States, fall‐winter (sport) harvests of goose species are estimated from federal surveys coordinated by the United States Fish and Wildlife Service, including the Migratory Bird Harvest Survey to estimate total goose harvest and the Parts Collection Survey (PCS) to estimate the species and age composition. For the PCS, randomly selected hunters collect tail and wing feathers of each goose shot during the hunting season, and then biologists determine the age class and species of each sample at organized events (Wingbees) in each of the 4 flyways (Pacific, Central, Mississippi, and Atlantic). For similarly colored goose species, cackling (Branta hutchinsii) versus Canada (B. canadensis) geese (dark geese) and Ross's (Anser rossii) versus snow (A. caerulescens) geese (light geese), different protocols evolved among Wingbees to differentiate samples into groupings of management interest, leading to difficulties in estimating species‐level harvests among the 4 flyways or nationally. We conducted a study among the United States flyways during 2019–2022 to derive thresholds of central tail feather length to discriminate between dark geese and between light geese. We compared morphological‐ and genetic‐based approaches. There was support for 2 distinct mitochondrial DNA (mtDNA) clades in dark and light geese, but only dark goose clades corresponded with central tail feather lengths (morphological size and species identification). Derived thresholds for central tail feather lengths of dark geese in the 3 westernmost flyways using genetic‐based species' discrimination were 145 mm for adults and 134 mm for juveniles, approximately 13 mm and 9 mm less, respectively, than thresholds using morphological‐based species' discrimination. There was limited ability to discriminate light geese based on either mtDNA or central tail feather lengths. We suggest managers use our derived thresholds based on genetic‐based species' discrimination to classify dark goose PCS samples. More advanced genome analyses should be conducted before changing current Wingbee protocols for light geese. Lastly, we encourage more studies to incorporate genetic analyses to complement morphological discrimination. [ABSTRACT FROM AUTHOR]

Conversion of natural habitats to urban landscapes is happening at a rapid pace around the globe. Establishing a preserve system and restoring lands within these preserves is one way to offset the loss of natural habitats. However, often when preserves are being developed little data exists outlining the distribution of species and the habitat parameters on which they depend. We used populations of the Cactus Wren (Campylorhynchus hrunneicapillus sandiegensis) inhabiting the coastal slope of California to demonstrate how to refine the general gestalt of habitat conditions for the wren into defined parameters that can be used to develop strategic restoration plans. We found that wren habitat use declined to nearly 0% when cactus patches were spaced farther than 800 m apart, regardless of size. The probability of occupancy, or habitat use. rose above 60% when cactus patches were 0.15 ha in size or greater. Elderberry is an important factor in areas with little topographic relief, as it provides perching sites. Buckwheat may not be important to the wren but could be used to select sites that have drier conditions conducive to cacti. Planting cactus to restore ruderal sites properly selected for xeric conditions, and within relatively close proximity to each other, could help meet conservation goals of connecting and increasing wren populations by establishing ecological functions at a landscape level. Received 2 December 2019. Accepted I October 2021. Key words: cholla, habitat restoration, occupancy, prickly pear cactus, sage scrub. La conversion de habitats naturales a ambientes urbanos csta ocurriendo a un paso acelerado en todo el mundo. El cstableeimiento de un sistema de reservas y la restauracion de tierras al interior de cstas rescrvas es una forma de contrarrcstar la perdida dc habitats naturales. Sin embargo, el desarrollo de reservas con frecuencia dispone de pocos datos que definan la distribucion de las especies y los parametros del habitat de los cuales dependen. Usamos poblaciones de la matraca Campylorhynchus hrunneicapillus sandiegensis que habita en la venicnte costera de California para demostrar como se puede refinar la pcrcepcion general de condiciones dc habitat de esta matraca en parametros definidos que puedan ser usados cn el desarrollo dc planes estrategicos dc restauracion. Encontramos que el uso de habitat de la matraca declino a cerca de 0% cuando los parches de cactus estaban espaeiados a distancias mayores de 800 m entre si, independicntemente de su tamaho. La probabilidad de ocupacion o de uso de habitat se elevo a mas de 60% cuando los parches dc cactus tenian tamahos de 0.15 ha o mayores. El sauco es un factor imponante en areas eon poea pendicnte, pues provee sitios para perchar. El alforfon podria no ser dc importancia para la matraca pero podria ser utilizado para seleccionar sitios que tiencn condiciones mas sccas y proclives a los cactus. La siembra de cactus para restaurar sitios ruderalcs apropiadamente seleccionados para condiciones xericas, y con una relativa cercania unos de otros. podria ayudar a alcanzar las metas de conservacion de conectar c incrcmcntar las poblaciones de matracas a traves del cstableeimiento de nanciones ecologicas en nivel dc paisaje. Palabras clave: cholla. matorral costero. nopales, ocupacion, restauracion de habitat., Conversion of natural habitats to urban landscapes is happening at a rapid pace around the globe (Ramalho and Hobbs 2012). In the latter part of the 20th century, urbanization has [...]

The San Bernardino flying squirrel (SBFS) is an isolated subspecies of Humboldt's flying squirrel, occurring in montane sky islands in the San Bernardino and San Jacinto Mountains in Southern California, USA. Recent small mammal surveys in the San Jacinto Mountains suggest the squirrel is extirpated. Our objectives were (1) determine habitat features, including forest metrics and topographical factors, that influence SBFS presence, in the San Bernardino Mountains; (2) use information collected in the San Bernardino Mountains to confirm squirrel occurrence and habitat preference in the San Jacinto Mountains; and (3) assess habitat and climatic differences between the two mountain ranges that could explain species persistence in one mountain range but not the other. We surveyed for SBFS using camera traps at 54 sites in the San Bernardino Mountains and 34 sites in the San Jacinto Mountains using both camera traps and acoustics. In the San Bernardino Mountains, we detected squirrels in sites that were more mesic, had higher structural heterogeneity, and had greater amounts of downed woody material compared to non‐detection sites. Habitat parameters were similar between the two ranges; however, squirrels were not detected in the San Jacinto Mountains. Conditions in the San Jacinto Mountains were hotter and drier. Increased temperatures due to climate change could potentially explain the absence of flying squirrels in the San Jacinto Mountains. [ABSTRACT FROM AUTHOR]

Scaled quail (Callipepla squamata) decline caused by habitat loss and fragmentation increased interest in translocation to reestablish populations. Yet factors determining translocation success are poorly understood. We tested hypotheses concerning the influence of source population and variation in delayed release strategy (1–9 weeks) on mortality and dispersal of wild‐caught, translocated scaled quail. We trapped and translocated quail from 2016–2017 from source populations in the Edwards Plateau and Rolling Plains ecoregions to a large contiguous (>40,000 ha) release site in Knox County, Texas, USA. We evaluated mortality and dispersal of translocated females as a function of source population, holding time prior to release, age, release location, and year using a multi‐state mark‐recapture model with state uncertainty. Scaled quail translocated within the Rolling Plains were more likely to exhibit philopatry to the release site. Quail with longer holding times had higher mortality but lower dispersal rates. The Edwards Plateau is a suitable source site for translocation in the Rolling Plains. The reduced dispersal but higher mortality of translocated scaled quail associated with longer holding times creates a decision tradeoff for managers. [ABSTRACT FROM AUTHOR]

Evaluating sympatric habitat use of a mammal community can help determine intra- and inter-guild interactions and identify important habitats, potentially improving the management of these communities with a changing climate. Increasingly variable climatic patterns in Alaska, USA, are raising concerns of mismatched phenologies and altered ecosystem structures. We studied the occupancy of 10 mammal species over 15 months, via camera traps, occupying alpine areas of the Alaska Range in interior Alaska, from 2013 to 2014. We tested hypotheses about how habitat use of these species within and between groups varied by spatial and temporal covariates. Furthermore, we modeled two-species occupancy of brown bears (Ursus arctos Linnaeus, 1758) and gray wolves (Canis lupus Linnaeus, 1758) against different potential prey species. Our results suggest that medium-sized and large herbivore use was positively correlated with fine-scale covariates including rock, forb, and graminoid coverage. Large herbivore habitat use was also correlated with abiotic landscape covariates. Detection probabilities of predators and Dall's sheep (Ovis dalli dalli Nelson, 1884) was improved by camera traps on wildlife trails. Two-species models suggested co-occurrence of habitat use between brown bear--caribou (Rangifer tarandus (Linnaeus, 1758)) and gray wolf--caribou. Results demonstrate the sympatric habitat use by multiple groups of mammals within Alaskan alpine ecosystems and the importance of incorporating multiple groups and spatial scales when making management decisions. Key words: Alaska, herbivores, mammals, military lands, predators, occupancy models, time-lapse camera traps. L'evaluation de l'utilisation sympatrique d'habitats au sein d'une communaute de mammiferes peut aider a determiner les interactions intra- et inter-guildes et cerner les habitats importants, ce qui peut ameliorer la gestion de ces communautes dans un contexte de changements climatiques. Des regimes climatiques de plus en plus variables en Alaska (Etats-Unis) soulevent des inquietudes associees a l'inadaptation des cycles biologiques et la modification de la structure des ecosystemes. A l'aide de pieges photographiques, nous avons etudie les motifs d'occupation de 10 especes de mammiferes pendant 15 mois dans des zones alpines de la chaine de l'Alaska de l'interieur de l'Alaska, de 2013 a 2014. Nous avons verifie des hypotheses concernant les variations de l'utilisation d'habitats par ces especes au sein de groupes et entre ces derniers en fonction de covariables spatiales et temporelles. Nous avons en outre modelise l'occupation par deux especes, l'ours brun (Ursus arctos Linnaeus, 1758) et le loup gris (Canis lupus Linnaeus, 1758), par rapport a differentes especes de proies potentielles. Nos resultats donnent a penser que l'utilisation par des herbivores de moyenne et grande taille est positivement correlee a des covariables a echelle fine, dont le couvert rocheux, de plantes herbacees non graminoides et de plantes graminoides. L'utilisation de l'habitat par les grands herbivores est egalement correlee a des covariables abiotiques du paysage. L'installation de pieges photographiques dans des pistes empruntees par des animaux sauvages ameliore la probabilite de detection de predateurs et de mouflons de Dall (Ovis dalli dalli Nelson, 1884). Des modeles a deux especes indiqueraient une cooccurrence de l'utilisation d'habitats par les ours bruns et les caribous (Rangifer tarandus (Linnaeus, 1758)) et par les loups gris et les caribous. Les resultats demontrent une utilisation sympatrique d'habitats par differents groupes de mammiferes dans des ecosystemes alpins de l'Alaska et l'importance d'integrer differents groupes et echelles spatiales dans la prise de decisions de gestion de la faune. [Traduit par la Redaction] Mots-cles: Alaska, herbivores, mammiferes, terrains militaires, predateurs, modeles d'occupation, pieges photographiques a intervalles., Introduction Habitat use by a species is limited by available resources, interspecific interactions, climatic variations, and other natural and anthropogenic barriers (Berlow et al. 1999; Harley 2011; Ruell et al. [...]