Habitat structure influences the survival and predator-prey interactions of early juvenile red king crab Paralithodes camtschaticus

• Main Authors: Pirtle, Jodi L, Eckert, G L, Stoner, A W
• Format: Text
• Language: unknown
• Published: University of New Hampshire Scholars' Repository 2012
• Subjects: Red king crab · Paralithodes camtschaticus · Nursery habitat dynamics · Predator–prey interaction · Habitat complexity · Refuge · Gadus macrocephalus; Oceanography and Atmospheric Sciences and Meteorology; Pacific; Paralithodes camtschaticus; Red king crab
• Online Access: https://scholars.unh.edu/ccom/1098; http://www.int-res.com/abstracts/meps/v465/p169-184/

Highly structured nursery habitats promote the survival of juvenile stages of manyspecies by providing foraging opportunities and refuge from predators. Through integratedlaboratory and field experiments, we demonstrate that nursery habitat structure affects survivaland predator-prey interactions of red king crab Paralithodes camtschaticus. Crabs (<1 yr old[Age 0]; 8 to 10 mm carapace length [CL]) preferred complex biogenic habitats formed by structuralinvertebrates and macroalgae over structural mimics and sand in the absence of predators inlaboratory experiments, yet they associated with any available structural habitat when fish predatorswere present. Survival was higher in the presence of complex habitat for Age 0 crabs (5 to7.5 mm CL) with Pacific cod Gadus macrocephalus predators in the laboratory and for Age 0(4 to 8 mm CL) and Age 1 (16 to 28 mm CL) crabs with fish and invertebrate predators in the field.Crab activity and refuge response behavior varied with crab stage and habitat. Age 0 crabs werecryptic, avoiding predators by associating with habitat structure or remaining motionless in theabsence of structure, and were less likely to respond to an attack. In contrast, Age 1 crabs weremore likely to respond to an attacking predator and were less likely to remain motionless in theabsence of structural refuge, suggesting an ontogenetic shift in behavior. Complex habitats, crypticbehavior, and direct defense improve juvenile red king crab survival against certain predators,including demersal fishes.