Alternative methodology for handling and marking meso-mammals for short-term research

Abstract

We evaluated squeeze cages and water-soluble inks and dyes as methods for handling and marking of meso-mammals in a short-term capturerecapture study. Study animals exhibited no adverse physiological impacts from capture or marking techniques. We also observed no negative impacts on trap success for the duration of the study. We found these methods quick (5 minutes maximum hold time), safe (no observed injuries of animals or researchers) and reliable (effective marking and mark retention for a minimum of 12 days).

Capturing and Marking Raccoons for Individual Recognition in Camera Studies using Tail‐fur Clipping and Dyes

“…The sturdy, fixed‐form, restraint cone made of ½ inch hardware cloth in this study likely restricts raccoon movements to a greater degree and provides greater safety to researchers than does the more flexible, larger‐mesh handling cone constructed of wire netting initially developed by Stuewer (1943) and used, apparently without significant modification, by subsequent biologists (e.g., Haupert and Lindeen 1974). Similarly, in contrast to the high degree of control afforded by the restraint cone design in this study, Parker et al (2012) found that squeeze cages allowed too much raccoon movement to make fur clipping a marking technique option. As a stand‐alone method, the described immobilization technique could also potentially facilitate wildlife studies requiring access to animal fur or tissues; for example, genetic and follicle stress hormone sampling (e.g., Caudron et al 2007).…”

“…Depending on study context and propensity of individual raccoons to revisit monitored areas, markings could be restored upon animal recapture to extend this period, as results suggested that the likelihood of raccoon recapture is high. Raccoons have generally not been found to exhibit a negative trap response in previous studies, including those involving intrusive procedures (Hoffman and Gottschang 1977, Gehrt et al 2001, Beasley and Rhodes 2007, Parker et al 2012. Researchers should also be aware of the timing of the annual pelage molt, because this has obvious implications for the utility of any fur marking method.…”

“…For example, investigations of social relationships, such as dominance hierarchies or membership of travelling and foraging associations, require knowledge of individual animal histories (Barding and Nelson 2008). Marking individual meso‐mammals is also useful in generating animal density estimates using mark/recapture data (e.g., Parker et al 2012) and enabling investigations into the extent to which reproductive success differs between individuals (Clutton‐Brock and Sheldon 2010). Similarly, assessing individual variation in raccoon response following exposure to experimental stimuli (e.g., conditioned taste aversion trials with oral estrogen [Semel and Nicolaus 1992] or broadcast predator sounds [Suraci et al 2016]) could better inform management efforts designed to reduce raccoon depredation on imperilled resources.…”

“…Although a method for handling captured raccoons with restraint cones made from semi‐flexible wire netting was described some decades ago by Stuewer (1943), the use of fur clipping as a marking method for raccoons appears absent in published work. Similarly, although Parker et al (2012) describe methods for marking raccoons with colored hair dyes for individual recognition, their techniques were not designed for passive animal “recapture” via camera traps under nocturnal conditions. The combined use of the capture and marking techniques described in this study is unique and will have value in field studies requiring night‐time image capture of individual raccoons, as well as in animal handling relative to other methods traditionally used for meso‐mammals (Powell and Proulx 2003, Parker et al 2012).…”

Natural Habitat, Housing, and Restraint of Six Selected Neotropical Animals in Trinidad and Tobago with the Potential for Domestication

“…Physical restraint was achieved by holding them from their tails [75], and gloves should be worn when handling [66]. D. virginiana was restrained using a Tomahawk ® squeeze cage (50 × 27.5 × 30 cm) [78]. A number of different chemical restraint methods can be used such as ketamine hydrochloride (dose rate of 5 mg/kg) and xylazine (dose rate of 2 mg/kg) intramuscularly [70].…”