Does the association of young fishes with jellyfishes protect from predation?A report on a failure case due to damage to the jellyfish

Abstract

The fish-jellyfish association is regarded as a temporary symbiosis believed to protect the fishes from predators. Here we report on juvenile scads (Trachurus lathami) associated with the jellyfish Chrysaora lactea, opportunistically preyed on by the grouper Mycteroperca acutirostris while the medusa was being damaged. The predation instances occurred when a couple of the filefish Stephanolepis hispidus approached the jellyfish to nibble on its umbrella. The feeding of the filefish caused a momentary disturbance of the defensive association, perceived and capitalised on by the watchful grouper, an opportunistic and versatile hunter. Before and after the disturbance, the protection offered to the young fish by the jellyfish showed to be effective, which strengthens the hypothesis of defensive function of this association.A associação entre peixes e medusas é considerada uma simbiose temporária que protegeria os peixes contra predadores. Relatamos aqui a predação oportunista de juvenis de xixarro Trachurus lathami, associados à medusa Chrysaora lactea, pelo badejo-mira Mycteroperca acutirostris enquanto a medusa estava sendo danificada. Os eventos de predação ocorreram quando um casal do peixe-porco Stephanolepis hispidus se aproximou da medusa para alimentar-se de pequenas porções da sua umbrela. A alimentação dos peixes-porcos causou um distúrbio momentâneo na associação defensiva, percebido e aproveitado pelo atento badejo-mira, um predador versátil e oportunista. Antes e depois do distúrbio, a proteção conferida aos peixes juvenis pela medusa mostrou ser efetiva, fortalecendo a hipótese de função defensiva desta associação.

Activity, habitat use, feeding behavior, and diet of four sympatric species of Serranidae (Actinopterygii: Perciformes) in southeastern Brazil

“…Sazima (1986) pointed out that M. acutirostris (cited as M. rubra) is a predator species of benthic crustaceans and small fishes. The dying feigning feeding tactic described by Gibran (2004) for the comb grouper, and the behavioral observations made by Sazima (1986) and Bonaldo et al (2004), corroborate the classification of this serranid as a versatile and opportunistic predator.…”

“…Six individuals were capturing prey in the water column through a vertical lunge from the bottom to the surface (nine captures; see Fig. 1 of Bonaldo et al, 2004: 104 for a photo of the initial posture of this serranid in an ambush). Two individuals were stalking and lunging prey items and one of them was performing dying or illness feigning (cf.…”

“…Previous studies on M. acutirostris in Brazil, which employed a naturalist approach (see Sazima, 1986;Bonaldo et al, 2004;Gibran, 2004), provided additional information on the feeding tactics and opportunism in this species.…”

Benthic scavengers and predators of jellyfish, material for a review

“…Nevertheless, jellyfish continue to be depicted occasionally (see Arai 2005 for examples) as dead ends in the food chains of the sea and/or as a rare source of food for predators (e.g. Condon et al 2011), despite an increasing number of species of fishes (Redeke 1911, Luttenberger 1981, Gorelova & Grudtsev 1986, Kelley 1987, Ates 1988, Arai 1988, Zann 1988: 208, Cerqueira & Haimovici 1990, Hall 1992, Harbison 1993, Massuti et al 1998, Purcell & Arai 2001, Bonaldo et al 2004, Arai 2005, Orsi Relini et al 2010a, Orsi Relini et al 2010b, Chaves et al 2010, Thaler 2012, Cardona et al 2012, Milisenda et al 2014, Battaglia et al 2014, Sweetman et al 2014, Dias & Almeida 2015, birds, reptiles and mammals (Dathe 1989, Ates 1991, Gronert 1992, Shiomi & Ogi 1992, Bell 1996, Zonfrillo 1997, Peglow 1998, Corsi 2000, Arai 2005, Suazo 2008, Cardona et al 2012, Jarman et al 2013, Melville 2013, Jones & Seminoff 2013, other cnidarians and ctenophores …”

Ocean acidification alters fish–jellyfish symbiosis

“…This association is particularly advantageous for larval and juvenile fish species during their oceanic life stage, because any type of pelagic habitat that provides protection from predation (e.g. driftwood, jellyfish, floating seaweed) can minimize early-life mortality [11,12].…”