![]() ![]() In addition, the debate as to whether increased predation following the recovery of many predator species in North America and Europe reduces opportunities for game hunting is ongoing (Forrester & Wittmer, 2013 Jonzén et al., 2013 Ripple et al., 2019). In North America, predation is sometimes identified as an underlying cause of decline for ungulate populations, often secondary to effects of weather and forage (Brodie et al., 2013 Forrester & Wittmer, 2013 Lukacs et al., 2018), or via apparent competition where the species impacted by predation is usually of conservation concern (e.g., Johnson et al., 2013 Wittmer et al., 2005). Incorrectly categorizing causes of mortality could result in biased survival probabilities (Marescot et al., 2015) and carries management and conservation implications for both predators and prey (e.g., increased carnivore control and decreased ungulate hunting Proffitt et al., 2020). While there have been many recent advances in methods used to accurately estimate vital rates and population size from various data sources (Silvy, 2012), little research focus is currently directed at the importance of correctly identifying the causes of observed mortalities of telemetered animals. For example, quantifying vital rates such as age-specific survival and estimating population size are fundamental to understanding the dynamics of animal populations (Caughley, 1994 Gaillard et al., 2000), but require accurate cause-specific mortality parameters derived from field-based evidence. There is, however, cause for concern that eroding ecoliteracy surrounding the study of organisms and their linkages to the environment is impacting our ability to conduct accurate ecological research (Middendorf & Pohlad, 2014 Tewksbury et al., 2014). We invite reviewers and journal editors to encourage authors to provide supportive information associated with the identification of causes of mortality, including uncertainty.Įcological research is inherently data driven and has been traditionally based on direct observations collected in the field. We discuss the need for rigorous and standardized protocols that include measures of confidence for mortality site investigations. Rapid site visitations significantly improved the successful identification of the cause of mortality and confidence levels for neonates. Over the course of our study, we visited mortality sites of neonates ( n = 91) and adults ( n = 23) to ascertain the cause of mortality. We demonstrate the importance of rigorous protocols and prompt site investigations using data from our 5-year study on survival and cause-specific mortality of telemetered mule deer ( Odocoileus hemionus) in northern California. We also outline how uncertainty in identifying the cause of mortality could be acknowledged and reported. ![]() Specifically, we highlight data that can be useful to differentiate predation from scavenging and more conclusively identify the predator species that killed the ungulate. ![]() We outline a step-by-step procedure for mortality site investigations of telemetered ungulates, including evidence that should be documented in the field. ![]() Field protocols used to investigate mortality sites and ascertain the cause of mortality are often minimally described and frequently fail to address how investigators dealt with uncertainty. This concise review revealed extensive variation in reporting of field procedures, with many studies omitting critical information for the cause of mortality inference. We reviewed a random sample of 50 peer-reviewed studies published between 20 on survival and cause-specific mortality of ungulates monitored with telemetry devices. Yet, eroding ecoliteracy and a lack of quality control in data collection can lead researchers to make incorrect conclusions, which may negatively impact management decisions for wildlife populations. Mortality site investigations of telemetered wildlife are important for cause-specific survival analyses and understanding underlying causes of observed population dynamics. ![]()
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