Nest building and description of parental care behavior in a temperate reef fish, Chromis crusma (Pisces: Pomacentridae)

Abstract

Background: Subtle ecological and behavioral mechanisms that enhance reproduction such as nest building by animals may provide useful information of population level processes. Variation in behavioral traits may be observed as phenotypic traits that are shaped by sexual and natural selection. Using ecological sampling of benthic substrata and underwater video recordings, we assessed nest-building behavior through habitat modifications, and size of individuals performing parental care behavior and egg/hatching traits of an abundant temperate reef fish, Chromis crusma. Results: We identified that only male individuals performed nest building and uniparental care. We noted that nests containing filamentous green or red algae had the highest percent cover of eggs. Using video recordings, we provided evidence of parental care. Male individuals spent nearly 80% of their time inside the nest, aerating the eggs with their fins and mouth, removing unwanted materials, and defending the nest against conspecific, heterospecific, and other predators. The field-collected eggs, characterized by an oil globule and adhesive filaments, hatched after 7 days in the laboratory. The nest-building and parental care behavior of C. crusma lasted for 3 months, and several nests can be constructed throughout the season. Conclusion:The behavior of building and defending the nests, which is a characteristic of the family members, is a key aspect for the success of the C. crusma; this fish is abundant in kelp ecosystems of the southeastern Pacific.

Embryonic and larval traits of the temperate damselfish Chromis crusma reveal important similarities with other Pomacentridae throughout the family's thermal range

“…15 m; Tapia et al, ). This period is the mid‐spawning season for C. crusma , as the first nests are usually observed during early October and the last ones around late March (Navarrete‐Fernández et al, ). Larvae hatched after 5–11 days, with yolk reserves lasting for only around 7 days.…”

“…Eggs were collected from five nests (n = 100 eggs per nest) at observably similar developmental stages (Kingsford, 1985) from vertical walls and hard substrata 21-25 m in depth (12 C; registered with dive computer). All nests were guarded by males (Navarrete-Fernández et al, 2014). Once collected, eggs from each nest were individually stored in 1 l glass jars and kept inside a plastic container covered with ice-packs to maintain a constant temperature of c. 11-12 C, avoiding potential changes in water temperature during transportation that could affect rates of embryonic development.…”

“…Eggs for this study were collected in February (mid-austral summer), when the seawater temperature had already reached c. 12-13 C at the collection depth (c. 15 m; Tapia et al, 2014). This period is the mid-spawning season for C. crusma, as the first nests are usually observed during early October and the last ones around late March (Navarrete-Fernández et al, 2014). Larvae hatched after 5-11 days, with yolk reserves lasting for only around 7 days.…”

“…21–25 cm diameter) and the associated parental care (Navarrete‐Fernández et al, ). Previous studies have described several aspects of the biology (Greenfield & Woods, ), trophic ecology (Aguilar‐Medrano et al, ; Angel & Ojeda, ; Fariña et al, ; Pequeño et al, ; Pérez‐Matus et al, ) and reproductive ecology (Navarrete‐Fernández et al, ) of C. crusma , but the early life history, ontogenesis, larval morphology and ecological traits associated with reproduction remain poorly known. Nonetheless, early life stages, particularly yolk‐sac and pre‐flexion larvae, have been collected in nearshore waters in northern and central Chile (Díaz‐Astudillo et al, , ; Landaeta et al, ; Paredes et al, ), with recent light trapping surveys being used to capture postlarvae and juvenile stages of C. crusma (Carrasco et al, ; Díaz‐Astudillo et al, ).…”

“…As in all pomacentrids, this species is oviparous and lays demersal eggs (Allen, 1991;Murphy et al, 2007) attached to the substratum upon green or red filamentous or crustose algae. Males are responsible for nest building (c. 21-25 cm diameter) and the associated parental care (Navarrete-Fernández et al, 2014). Previous studies have described several aspects of the biology (Greenfield & Woods, 1980), trophic ecology (Aguilar-Medrano et al, 2013;Angel & Ojeda, 2001;Fariña et al, 2008;Pequeño et al, 2005;Pérez-Matus et al, 2007) and reproductive ecology (Navarrete-Fernández et al, 2014) of C. crusma, but the early life history, ontogenesis, larval morphology and ecological traits associated with reproduction remain poorly known.…”