Overduin Sienna L, Killen Shaun S, Zimmer Alex M, McCuaig Jenelle D, Cotgrove Lucy, Aragao Isabel, Rozanitis Kelly J, Konhauser Kurt O, Alessi Daniel S, Blewett Tamzin A
Department of Biological Sciences, University of Alberta, Edmonton T6G 2E9, Canada; Bamfield Marine Sciences Centre, Bamfield, BC V0R 1B0, Canada.
School of Biodiversity, One Health, and Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, United Kingdom.
Ecotoxicol Environ Saf. 2025 Jan 1;289:117432. doi: 10.1016/j.ecoenv.2024.117432. Epub 2024 Dec 6.
Many species exhibit social living which offers ecological advantages such as increased foraging opportunities, more efficient locomotion and reduced predation risk. Additionally, exposure to multiple individuals of the same species can decrease an individual's stress and metabolic demand, termed social buffering. If disruption to an animal's social structure occurs and prevents social buffering, an elevated metabolic rate and thus ventilation frequency and gill permeability are likely. A potential consequence of this physiological response could be the increased accumulation of toxicants. The objective of this study was to investigate whether inducing social stress in marine threespine stickleback (Gasterosteus aculeatus) through social isolation during a sublethal water-borne copper (Cu) exposure would affect Cu uptake and whether that would translate to differences in behaviour and biochemical functioning. We hypothesized that isolating threespine stickleback during a Cu exposure would increase Cu uptake and sublethal toxicity compared to a grouped exposure. Wild-caught fish were exposed to control, low Cu or high Cu conditions (0 - 150 µg/L of Cu, nominally), either in isolation or groups of six for 96 h. Isolated stickleback travelled three times less distance, took six times longer to consume food and exhibited moderately increased gill sodium-potassium ATPase activity than group exposed fish, with no effect of Cu. Isolated stickleback also demonstrated significantly higher Cu levels in their gill and liver tissue compared to the group exposed fish. However, this Cu distribution was also present within the control fish, which had not been exposed to Cu, suggesting that the social context affects endogenous Cu distribution under stressful conditions. Our results illustrate the differences in physiology and behaviour that can arise when social contexts are manipulated and stress the importance of considering sociality when conducting toxicity tests with social organisms.
许多物种表现出群居生活，这带来了生态优势，如觅食机会增加、行动更高效以及被捕食风险降低。此外，接触同物种的多个个体可降低个体的压力和代谢需求，这被称为社会缓冲。如果动物的社会结构受到破坏并阻碍了社会缓冲，那么代谢率很可能会升高，从而导致呼吸频率和鳃通透性增加。这种生理反应的一个潜在后果可能是有毒物质积累增加。本研究的目的是调查在亚致死性水体铜（Cu）暴露期间，通过社会隔离对海洋三刺鱼（Gasterosteus aculeatus）施加社会压力是否会影响铜的吸收，以及这是否会转化为行为和生化功能的差异。我们假设，与群体暴露相比，在铜暴露期间隔离三刺鱼会增加铜的吸收和亚致死毒性。将野生捕获的鱼分别单独或分成每组六条，暴露于对照、低铜或高铜条件下（名义上为0 - 150μg/L的铜）96小时。与群体暴露的鱼相比，隔离的三刺鱼游动的距离减少了三倍，进食时间延长了六倍，鳃钠钾ATP酶活性略有增加，且不受铜的影响。与群体暴露的鱼相比，隔离的三刺鱼鳃和肝脏组织中的铜含量也显著更高。然而，这种铜的分布在未接触铜的对照鱼中也存在，这表明社会环境会在应激条件下影响内源性铜的分布。我们的结果说明了操纵社会环境时可能出现的生理和行为差异，并强调了在对群居生物进行毒性测试时考虑社会性的重要性。
