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The advent of new technologies and statistical analyses has provided valuable insights into chondrichthyan social behavior. It has become apparent that sharks and rays lead more complex social lives than previously believed. Heterarchy combines hierarchy and social network theory and although it is not a new concept, it is rarely applied to animal social interactions. Here, we applied heterarchy to a case study involving smooth stingrays foraging for fish scraps at boat ramp in Jervis Bay, NSW Australia. We took advantage of their attraction to this site to examine their social behavior during agonistic interactions over the provisioned resource. We observed a stable, relatively linear but shallow dominance hierarchy that was highly transitive dominated by a single individual. Social network analysis revealed a non-random social network centered on the dominant individual. Contrary to previous research, size did not predict dominance, but it was correlated with network centrality. The factors determining dominance of lower ranks were difficult to discern, which is characteristic of despotic societies. This study provides the first heterarchical assessment of stingray sociality, and suggests this species is capable of complex social behavior. Given higher dominance and centrality relate to greater access to the provisioned resource, the observed social structure likely has fitness implications.

Context. It is common for recreational anglers to discard waste produced from filleting catches back into the water, which results in a highly spatio-temporally predictable food subsidy for wildlife to scavenge. However, the behavioural responses of these scavengers has received little attention. Aims. We aimed to assess the visitation of a common mesopredatory scavenger in relation to temporal patterns in waste discarding at a boat ramp in south-eastern Australia. Methods. Using passive acoustic telemetry, the movements of 13 adult female smooth stingrays (Bathytoshia brevicaudata) were tracked, and patterns in their acoustic detections and duration of time spent in different sections within the study area were compared. Key results. Use of the study area was strongly focused around the boat ramp, and peaked during periods of increased provisioning activity (i.e. afternoons and weekends). Environmental variables had limited influence on visitation, suggesting that the use of the area was not likely to be linked to natural behaviours. Conclusions. The observed patterns indicated that the movements of smooth stingrays were linked to waste-discard practices by recreational anglers. Implications. This study has implications for the management of discard practices for recreational fishing.

Since 2012, there has been a surge in the numbers of marine science publications that use the term ‘best practice’, yet the term is not often defined, nor is the process behind the best practice development described. Importantly a ‘best practice’ is more than a documented practice that an individual or institution uses and considers good. This article describes a rigorous process to develop an ocean best practice using examples from a case study from Australia in which a suite of nine standard operating procedures were released in 2018 and have since become national best practices. The process to develop a best practice includes three phases 1) scope and recruit, 2) develop and release, 3) revise and ratify. Each phase includes 2-3 steps and associated actions that are supported by the Ocean Best Practices System (www.oceanbestpractices.org). The Australian case study differs from many other practices, which only use the second phase (develop and release). In this article, we emphasize the value of the other phases to ensure a practice is truly a ‘best practice’. These phases also have other benefits, including higher uptake of a practice stemming from a sense of shared ownership (from scope and recruit phase) and currency and accuracy (from revise and ratify phase). Although the process described in this paper may be challenging and time-consuming, it optimizes the chance to develop a true best practice that is a) fit-for-purpose with clearly defined scope; b) representative and inclusive of potential users; c) accurate and effective, reflecting emerging technologies and programs; and d) supported and adopted by users.

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