Feeding habits and dietary overlap during the larval development of two sandperches (Pisces: Pinguipedidae)

Abstract

Summary:Two species of sandperch (Pinguipedidae: Perciformes), Prolatilus jugularis and Pinguipes chilensis, inhabit the coastal waters of the South Pacific. Both species have pelagic larvae with similar morphology, but their diet preferences are unknown. Diet composition, feeding success, trophic niche breadth and dietary overlap were described during larval stages for both species. In the austral spring, larval P. jugularis (3.83-10.80 mm standard length [SL]) and P. chilensis (3.49-7.71 mm SL) during their first month of life had a high feeding incidence (>70%) and fed mostly on copepod nauplii (>80% IRI), Rhincalanus nasutus metanauplii and Paracalanus indicus copepodites. The number of prey ingested was low (mean: 4-5 prey per gut) and independent of larval size; total prey volume and maximum prey width increased as larvae grew. Mouth opening and ingested prey were greater in larval P. jugularis than in P. chilensis, leading to significant differences in prey composition among larval species, in terms of prey number and volume. Pearre's trophic niche breadth was narrow for both species (0.159±0.07 for P. jugularis; 0.156±0.03 for P. chilensis) and independent of larval size. Dietary overlap was high inter-and intra-species in larvae with a mouth gape <900 μm. These results suggest the relative importance of both larval species as primary consumers of the pelagic web in nearshore environments of rocky temperate areas.Keywords: Prolatilus jugularis; Pinguipes chilensis; sandperch, feeding; resource partitioning; Chile.Hábitos alimentarios y superposición de la dieta durante el desarrollo larval de dos blanquillos (Pisces: Pinguipedidae) Resumen: Existen dos especies de blanquillo (Pinguipedidae: Perciformes), Prolatilus jugularis y Pinguipes chilensis que habitan las aguas costeras del Pacífico Sur. Ambas especies tienen larvas pelágicas con morfología similar, pero se desconocen sus preferencias de la dieta. Se describen la composición de la dieta, amplitud del nicho trófico y superposición trófica durante los estados larvales de ambas especies. En primavera, las larvas de P. jugularis (3.83-10.80 mm LE) y P. chilensis (3.49-7.71 mm LE) durante su primer mes de vida tienen alta incidencia alimentaria (>70%) y se alimentan principalmente de nauplii de copépodos (>80%IRI), metanauplii de Rhincalanus nasutus y copepoditos de Paracalanus indicus. El número de presas ingeridas fue bajo (media: 4-5 presas por estómago) e independiente del tamaño larval; el volumen total de presas y el ancho máximo de las presas se incrementó a medida que crecían las larvas de ambas especies. El largo de la mandíbula y el tamaño de las presas fue más grande en larvas de P. jugularis comparado con las de P. chilensis. Esto generó diferencias significativas en la composición de las presas entre especies, en términos de número y volumen de las presas ingeridas. La amplitud del nicho trófico de Pearre fue bajo para ambas especies (0.159±0.07 para P. jugularis; 0.156±0.03 para P. chilensis) e independiente del tamaño larval. La superpos...

Lunar influences in the diet habits and selectivity of larval clingfish Gobiesox marmoratus

“…This suggests resource partitioning between both sympatric species during their pelagic stages. Other marine fish species with pelagic larval stages from central Chile [anchoveta, sandperches (Pinguipedidae), blennies (Labrisomidae)] also fed mostly on early stages of calanoid copepods [eggs, nauplii, copepodites (Balbontín et al ., ; Vera‐Duarte & Landaeta, , )], highlighting the difference in foraging behaviour of larval G. marmoratus .…”