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Molt migration is an annual movement from the breeding grounds to a different, distant molting area often north of the breeding grounds. Such movements are only completed by a segment of a population, typically nonbreeding individuals or failed breeders. Although moll migration is common among waterfowl, especially largebodied species such as geese, it remains unknown whether the Trumpeter Swan (Cygnus buccinator), a species whose population is rapidly growing and expanding throughout the mid-continental United States, engages in molt migration. Here, we provide the first empirical description of an apparent molt migration of a nonbreeding male Trumpeter Swan using location data collected by a GPS-GSM collar. The swan departed its natal wetland in north-central Iowa, USA. on 1 June 2019 and arrived at a complex of small wetlands near Great Slave Lake in the Northwest Territories, Canada, on 4 July 2019. a straight-line distance of 2.420 km. For the next 43 d. the swan restricted its movements to a small wetland with a mean distance between sequential points of 126.15 m (range = 0.33-2,910.72 m). suggesting it was flightless during this time period. Both the timing and duration of this presumed flightless period coincide with the second prebasic molt in swans. Received 5 May 2021. Accepted 10 February 2022. Key words: GPS-GSM transmitter, Iowa, movement. reintroduction. waterfowl. La muda durante la migracion es un movimicnto anual del area de reproduccion a una diferente area para la muda. freeuentemente al norte de sus areas reproductivas. Dichos movimientos soiatnente son completados por un segmento dc la poblacidn, lipicamente individuos no-reproductivos o anidantes fallidos. Aunque la muda durante la migracion es comiin entre aves acuatieas, especialmente espeeies de tamano grande eomo los gansos, aun desconocemos si el cisne Cygnus buccinator, una especie cuya poblacidn esta creciendo rapidamente y expandiendose a lo largo dc la region continental media de los Estados LInidos. tiene muda de migracion. Aqui damns la primera descripcidn empirica de una aparente muda de migracion en un macho no-rcproductivo de este cisne, usando datos dc localidadcs colecladas por medio de un collar GPS-GSM. El cisne partid de su humedal natal en Iowa norcentral, EUA, el 1 de junio de 2019 y llego a un complejo dc pequenos humedalcs ccrca del lago Great Slave en Northwest Territories, Canada, el 4 de Julio de 201[degrees]. una distaneia lineal de 2,420 km. Por los proximos 43 d. el cisne limitd sus movimientos a un pequeno humedal con una distaneia lineal entre puntos secueneiales de 126.15 m (rango = 0.33-2.910.72 m). lo que sugierc que no podia volar durante este periodo. Ambos, la temporalidad y duration de este periodo presumiblcmcnte sin volar coineiden eon la segunda muda prebasica en cisnes. Palabras clave: aves acuatieas, Iowa, movimicnto, reintroduceion, transmisor GPS-GSM., Migration is characterized as a seasonal movement from one region to another. Although extensive discussion exists on exactly how migration evolved among different bird species (e.g., the direction, duration, and [...]

Predictions of species occurrence allow land managers to focus conservation efforts on locations where species are most likely to occur. Such analyses are rare for herpetofauna compared to other taxa, despite increasing evidence that herptile populations are declining because of landcover change and habitat fragmentation. Our objective was to create predictions of occupancy and colonization probabilities for 15 herptiles of greatest conservation need in Iowa. From 2006–2014, we surveyed 295 properties throughout Iowa for herptile presence using timed visual-encounter surveys, coverboards, and aquatic traps. Data were analyzed using robust design occupancy modeling with landscape-level covariates. Occupancy ranged from 0.01 (95% CI = -0.01, 0.03) for prairie ringneck snake (Diadophis punctatus arnyi) to 0.90 (95% CI = 0.898, 0.904) for northern leopard frog (Lithobates pipiens). Occupancy for most species correlated to landscape features at the 1-km scale. General patterns of species' occupancy included negative effects of agricultural features and positive effects of water features on turtles and frogs. Colonization probabilities ranged from 0.007 (95% CI = 0.006, 0.008) for spiny softshell turtle (Apalone spinifera) to 0.82 (95% CI = 0.62, 1.0) for western fox snake (Pantherophis ramspotti). Colonization probabilities for most species were best explained by effects of water and grassland landscape features. Predictive models had strong support (AUC > 0.70) for six out of 15 species (40%), including all three turtles studied. Our results provide estimates of occupancy and colonization probabilities and spatial predictions of occurrence for herptiles of greatest conservation need across the state of Iowa. [ABSTRACT FROM AUTHOR]

Weather conditions, such as temperature and precipitation, likely influence white‐tailed deer (Odocoileus virginianus) activity and hunter participation, both of which are major factors contributing to deer harvest. Because harvest is often used to manage white‐tailed deer population trends and guide management decisions, understanding how certain abiotic factors may bias such data is important. We examined the effects of weather on deer harvest during the Iowa, USA, firearms seasons from 2006–2021 using a generalized mixed‐effects linear model. Weather conditions during the hunting season were related to overall deer harvest. Specifically, deer harvest was positively correlated with snowfall on opening day and negatively correlated with average minimum temperature, average snow depth, rainfall on opening day, and number of rainfall and snowfall days. Abiotic factors have the ability to substantially influence deer harvest. Because many white‐tailed deer population models use harvest data, incorporating the effects of weather variability into such models may substantially improve population estimates. Our study provides a compelling case for considering hunting season weather conditions when interpreting harvest data as a population index for white‐tailed deer. The results of this study also demonstrate potential for retrospective modeling of past harvest rates and incorporating the effects of abiotic factors on harvest into future age‐based population models. [ABSTRACT FROM AUTHOR]