ABSTRACT
The occurrence of plastic ingestion by fish is increasing around the world, however there are currently very few studies focusing on the ingestion of macro (>20 mm) and mega (>100 mm) plastics in pelagic predatory fish, particularly in Australian waters. Further to this, information on plastic ingestion in recreationally caught fish is deficient. We report on two cases of macroplastic ingestion and another case of megaplastic ingestion by southern bluefin tuna Thunnus maccoyii (Castelnau, 1872), caught recreationally in Tasmania and Victoria. The plastics ingested ranged from 62 to 283 mm. Despite the large obstructive shapes of the pieces of plastic, all three specimens possessed a healthy body mass, with one actively feeding at the time of capture. These preliminary records contribute to the limited information on the effects of plastic pollution on high value recreationally and commercially important pelagic fish in Australia.
Subject(s)
Plastics , Tuna , Animals , Eating , South Australia/epidemiology , VictoriaABSTRACT
Globally, collapse of ecosystems-potentially irreversible change to ecosystem structure, composition and function-imperils biodiversity, human health and well-being. We examine the current state and recent trajectories of 19 ecosystems, spanning 58° of latitude across 7.7 M km2 , from Australia's coral reefs to terrestrial Antarctica. Pressures from global climate change and regional human impacts, occurring as chronic 'presses' and/or acute 'pulses', drive ecosystem collapse. Ecosystem responses to 5-17 pressures were categorised as four collapse profiles-abrupt, smooth, stepped and fluctuating. The manifestation of widespread ecosystem collapse is a stark warning of the necessity to take action. We present a three-step assessment and management framework (3As Pathway Awareness, Anticipation and Action) to aid strategic and effective mitigation to alleviate further degradation to help secure our future.
