Predators Reject Yellow Perch Egg Skeins

Abstract

Despite the high rate of egg mortality due to predation, few teleost fishes utilize external casings for protecting their eggs. The gelatinous egg matrix, or skein, produced by Yellow Perch Perca flavescens may provide a variety of benefits including deterring egg predators. This study explored the chemical components of the skein in addition to testing the preferences of two common egg predators, Round Goby Neogobius melanostomus and calico crayfish Orconectes immunis, when presented with three potential egg prey: Yellow Perch eggs in the skein, Yellow Perch eggs without the skein, and Fathead Minnow Pimephales promelas eggs. Preliminary analyses showed that the skein may contain a variety of potentially noxious components, including piperideine and the galactose-specific lectin, nattectin. In preference trials, Yellow Perch eggs in the skein were often approached first; however, both predators preferred Yellow Perch eggs with the skein removed and Fathead Minnow eggs rather than Yellow Perch eggs in the skein. Further experiments demonstrated that crayfish spent less time attempting to consume Yellow Perch eggs in the skein after prior exposure to the skein (day 1: 11.0 min ± 1.3 [mean ± SE]; day 2: 7.6 min ± 1.4), reducing time spent damaging the eggs. These results indicate that the skein may help protect eggs from predation.

Assessing the effects of sub‐tropical winter thermal conditions on coolwater fish reproduction

“…Together these results suggest positive effects of cold, long winters on egg production and larval quality, similar to findings in studies with Yellow Perch (Farmer et al, 2015) and other cool-and coldwater fishes (Burt et al, 2011). However, we also found that egg quality, measured by energetic density, was higher following warm winters Warmer winter temperature had a positive effect on caloric density (p = .011), but winter duration did not impact caloric density in eggs of eggs and egg skein (Almeida et al, 2017). A more robust egg skein could be beneficial in colder environments to protect eggs from predators or to keep eggs attached to vegetation for longer durations when spawning occurs at colder temperatures and the incubation period is longer (Almeida et al, 2017;Hart et al, 2006).…”

“…The increase in, presumably, lower energy‐rich egg skein matrix could potentially explain both the larger egg skein mass and the lower total egg skein caloric density produced after colder winters. Due to the adhesive antipredator properties of the gelatinous egg skein matrix, it is difficult to extract eggs from the matrix material for independent measurements of eggs and egg skein (Almeida et al, 2017). A more robust egg skein could be beneficial in colder environments to protect eggs from predators or to keep eggs attached to vegetation for longer durations when spawning occurs at colder temperatures and the incubation period is longer (Almeida et al, 2017; Hart et al, 2006).…”

“…Due to the adhesive antipredator properties of the gelatinous egg skein matrix, it is difficult to extract eggs from the matrix material for independent measurements of eggs and egg skein (Almeida et al, 2017). A more robust egg skein could be beneficial in colder environments to protect eggs from predators or to keep eggs attached to vegetation for longer durations when spawning occurs at colder temperatures and the incubation period is longer (Almeida et al, 2017; Hart et al, 2006). When winter duration was similar, larger larvae were produced following colder winter minimum temperatures, suggesting thermally based differences in female energy allocation per offspring or that colder incubation temperatures resulted in larger larvae, as previously observed for other species (Bengston et al, 1987).…”

15. The Comparative Toxicity of two Canadian Diluted Bitumens to Developing Yellow Perch (Perca flavescens)

“…Yellow perch embryos differ from species used in previous toxicity tests (Madison et al 2015;2017); their eggs are connected in a gelatinous, strand-like mass that is laid in ribbons. Yellow perch are the only known North American fish to produce a protective jelly coat, which may allow them to avoid intensive predation (Almeida et al 2017). At lower volumes of dilbit, this jelly coat may protect yellow perch embryos from PAH absorption and reduce the bioavailability of these compounds.…”

On ability of perch to colonize new waterbodies — indirect evidence and sticky facts. A Comment on: ‘Multiple lines and levels of evidence for avian zoochory promoting fish colonization of artificial lakes’ (2023), by Garcia et al .

“…Several studies have, however, shown that the egg ribbons of both Eurasian perch and yellow perch (Perca flavescens) deter a variety of teleost (except Wels catfish) [7] and invertebrate predators because of unpalatability [8,9]. Furthermore, analysis of eggshells and the egg matrix in yellow perch has revealed a high concentration of a variety of potentially noxious components, including piperideine and nattectin [8]. Yet, despite substantial evidence of an unappealing taste of perch egg ribbons to predators, this and the unique feature of the gelatinous egg matrix was overlooked by Garcia et al [1].…”