Welfare of Farmed Crocodilians: Identification of Potential Animal-Based Measures Using Elicitation of Expert Opinion

Abstract

Animal-based measures are the measure of choice in animal welfare assessment protocols as they can often be applied completely independently to the housing or production system employed. Although there has been a small body of work on potential animal-based measures for farmed crocodilians, they have not been studied in the context of an animal welfare assessment protocol. Potential animal-based measures that could be used to reflect the welfare state of farmed crocodilians were identified and aligned with the Welfare Quality® principles of good housing, good health, good feeding and appropriate behaviour. A consultation process with a panel of experts was used to evaluate and score the potential measures in terms of validity and feasibility. This resulted in a toolbox of measures being identified for further development and integration into animal welfare assessment on the farm. Animal-based measures related to ‘good feeding’ and ‘good health’ received the highest scores for validity and feasibility by the experts. There was less agreement on the animal-based measures that could be used to reflect ‘appropriate behaviour’. Where no animal-based measures were deemed to reliably reflect a welfare criterion nor be useful as a measure on the farm, additional measures of resources or management were suggested as alternatives. Future work in this area should focus on the reliability of the proposed measures and involve further evaluation of their validity and feasibility as they relate to different species of crocodilian and farming system.

Behaviours of farmed saltwater crocodiles (Crocodylus porosus) housed individually or in groups

“…Crocodile eggs are predominantly wild-harvested and are hatched on farm, where optimised conditions ( 2 , 3 ) are essential for maximising hatchling survival and skin quality and thus the economic viability of the commercial industry ( 1 , 4 ). Similar to societal pressures faced by other farmed livestock, the welfare of farmed crocodilians is a growing concern, with increasing pressure on the global industry to optimise animal welfare and develop standards and guidelines for management ( 5 ). However, there is as yet very little understanding of the behavioural ecology of captive saltwater crocodiles including what resources they desire or require under captive management.…”

“…With regard to farmed crocodiles, there is little information on what they ‘want’ as research in commercial settings is limited. It is unclear whether farmed crocodiles would benefit from social interactions with others and whether group housing during the finishing stage would facilitate positive affiliative or negative aggressive behaviours ( 5 ). Furthermore, there is limited research on whether farmed crocodiles require additional mental stimulation beyond feeding such as that provided through social interaction ( 7 , 19 ), or the agency of environmental choice between land and water, without social competition.…”