Ocean acidification alters fish–jellyfish symbiosis

Abstract

Symbiotic relationships are common in nature, and are important for individual fitness and sustaining species populations. Global change is rapidly altering environmental conditions, but, with the exception of coralmicroalgae interactions, we know little of how this will affect symbiotic relationships. We here test how the effects of ocean acidification, from rising anthropogenic CO 2 emissions, may alter symbiotic interactions between juvenile fish and their jellyfish hosts. Fishes treated with elevated seawater CO 2 concentrations, as forecast for the end of the century on a business-as-usual greenhouse gas emission scenario, were negatively affected in their behaviour. The total time that fish (yellowtail scad) spent close to their jellyfish host in a choice arena where they could see and smell their host was approximately three times shorter under future compared with ambient CO 2 conditions. Likewise, the mean number of attempts to associate with jellyfish was almost three times lower in CO 2 -treated compared with control fish, while only 63% (high CO 2 ) versus 86% (control) of all individuals tested initiated an association at all. By contrast, none of three fish species tested were attracted solely to jellyfish olfactory cues under present-day CO 2 conditions, suggesting that the altered fish-jellyfish association is not driven by negative effects of ocean acidification on olfaction. Because shelter is not widely available in the open water column and larvae of many (and often commercially important) pelagic species associate with jellyfish for protection against predators, modification of the fish-jellyfish symbiosis might lead to higher mortality and alter species population dynamics, and potentially have flow-on effects for their fisheries.

Pre-exposure to simultaneous, but not individual, climate change stressors limits acclimation capacity of Irukandji jellyfish polyps to predicted climate scenarios

“…These studies have generally documented negative effects on behaviour (Nagelkerken and Munday 2015;Nagelkerken et al 2016), physiology (Pörtner 2008), growth, and reproduction for most marine species (Harvey et al 2013;Kroeker et al 2013). Evidence is emerging, however, that biota may become more robust to changing ocean conditions over time via genetic adaptation (Munday et al 2013) and non-genetic processes such as acclimation (Munday 2014;van Oppen et al 2015;Foo and Byrne 2016).…”

<i>Euceramus transversilineatus</i> (Decapoda: Porcellanidae) living in the mantle lobe of the snail <i>Melongena patula</i> (Gastropoda: Melongenidae) in the south eastern Gulf of California: Inference of a biological association

“…Such interactions are classified as commensalistic, parasitic or mutualistic relationships and these interactions can be intra-or inter-specific (Rizzo & Lo-Giudice 2018). Biological associations between marine invertebrates represent strategies of evolutionary adaptation in response to selective pressures exerted by environmental conditions of the ocean, interaction between members of a community and more recently by anthropogenic effects and climate change (Nagelkerken et al 2016, Baker et al 2018. Invertebrates such as annelids, bryozoans, crustaceans and mollusks, among others, coexist in order to acquire refuge, food, and/ or reproductive niches (Baeza 2007, Beu & Zibrowius 2007, Ocampo et al 2014, Tenjing 2017.…”

Observations on the specific associations found between scyphomedusae and commensal fish and invertebrates in the Philippines

“…The jellyfish symbiotic interactions in the marine environment and effects on ecological processes are still poorly understood (Ohtsuka et al 2009). These animal associations are affected by natural and anthropogenic perturbations (Brotz et al 2016;Nagelkerken et al 2016). Ocean acidification as a mark of climate change threatens these animal associations by negatively affecting the behavior of commensals which take shelter with medusa hosts (Nagelkerken et al 2016).…”

“…These animal associations are affected by natural and anthropogenic perturbations (Brotz et al 2016;Nagelkerken et al 2016). Ocean acidification as a mark of climate change threatens these animal associations by negatively affecting the behavior of commensals which take shelter with medusa hosts (Nagelkerken et al 2016). Several species of edible jellyfish known to associate with animal commensals are harvested annually for large-scale commercial fisheries (Browne and Kingsford 2005;Ohtsuka et al 2009;Ohtsuka et al 4 2010; Brotz et al 2016).…”