Adaptive behaviour of fishers to external perturbations: simulation of the Tasmanian rock lobster fishery

Abstract

The rock lobster, Jasus edwardsii, lies on a global "hotspot" for climate change in the southeastern Australian state of Tasmania. The short-term effects of climate change are predicted to lead to an increasing exploitable biomass in the south and declining biomass in the north of the state. The future of the fishery is highly uncertain due to climate change, but also due to insecurities linked to the market conditions. The market for Tasmanian rock lobster is driven by the demand of a single market, China, which absorbs 75 % of the catch. This study examines how fishers can adapt to external perturbations that affect the social and economic viability of the fleet and the ecological dynamics of the stock. Three fleet dynamic models of increasing complexity are used to investigate the effects of climate change and lobster price changes on the fishery. There could be local depletion leading to negative short-term profit for the fleet if it is static and the proportion of the total catch taken in each region of the fishery does not respond to climate-induced-changes. Better outcomes would occur if the fleet adapts dynamically to environmental conditions, and fishing effort follows stock abundance, which would counteract the short-term effects of climate change. Only a model with explicit representation of economic drivers can fully capture the local economic and social impacts of large scale global perturbations.

Micro-economic drivers of profitability in an ITQ-managed fishery: An analysis of the Queensland Coral Reef Fin-Fish Fishery

“…catch rates) can be influenced by a combination of short-term and longer-term environmental and n Standard deviations in brackets; Source: own calculations based on Fisheries Queensland data. 7 This would seem to indicate the existence of transaction costs on this market which discourage trades from occurring, despite this leading to costs for quota owners who decide not to fish their quota themselves, in terms of both cash costs (annual administration fees payed on units owned) and opportunity costs of not leasing their quota out. See [20] for a more detailed analysis of the CT quota market characteristics.…”

“…This is because consideration of such responses may be critical in assessing the likely ecological, economic and social consequences of alternative management options [3][4][5][6], as well as of externally driven shocks such as climatic events [7]. In the fisheries modeling literature, as in the broader domain of fisheries research and policy analysis, the operators involved in commercial fishing are often referred to as "Fishermen" or "Fishers", with limited to no further specification.…”

Behavioural diversity in fishing—Towards a next generation of fishery models

“…The point has been made often enough to almost become a platitude: human behaviour is a key uncertainty for fisheries management, because it receives too little attention in conventional fisheries science and management (Fulton et al., 2011; van Putten, Kulmala, et al, 2012). Several excellent reviews of fishery models representing both fisher or fleet behaviour and fish population dynamics have recently proved this point (Fenichel et al., 2012; Girardin et al, 2017; Hamon, Frusher, Little, Thébaud, & Punt, 2014; van Putten, Kulmala, et al, 2012). They stress the need for a more realistic inclusion of human behaviour and, in particular, the dynamics of resource users.…”

Ocean warming hotspots provide early warning laboratories for climate change impacts

“…Melnychuk et al (2013) also concluded that hotspot regions contain fisheries that demonstrate the potential for adaptability to unpredictable climate impacts. Moreover, a case study in the rapidly warming region of south east Australia by Hamon et al (2013) demonstrates fisheries will need to respond to market conditions as well as the direct impacts of environmental changes. The fishery for southern rock lobster (Jasus edwardsii) operates within the south east Australian hotspot off the east coast of Tasmania.…”

“…The fishery for southern rock lobster (Jasus edwardsii) operates within the south east Australian hotspot off the east coast of Tasmania. Hamon et al (2013) point out that the future of the Tasmanian rock lobster fishery is highly uncertain due to climate change, but also due to insecurities linked to the market conditions. Three fleet dynamic models of increasing complexity were used to investigate the effects of climate change and lobster price changes on the fishery.…”