Distribution and diet of four species of carcharhinid shark in the Hawaiian Islands: evidence for resource partitioning and competitive exclusion

Competition and predation are both important in structuring the distribution of marine organisms; however, little is known about how competition and predation influence the distribution of elasmobranch fishes. We used data collected from shark control programs conducted between 1967 and 1980, throughout the Hawaiian island chain, to examine the distribution and dietary over- lap of the 4 most abundant carcharhinid sharks. Tiger sharks Galeorcerdo cuvier and Galapagos sharks Carcharhinus galapagensis were caught at all islands, but were more abundant in the north- western Hawaiian Islands (NWHI) than in the main Hawaiian Islands (MHI). Gray reef sharks Carcharhinus amblyrhynchos and sandbar sharks Carcharhinus plumbeus showed an inverse rela- tionship in distribution, with sandbar sharks abundant in the MHI, but virtually absent throughout the NWHI, and gray reef sharks only sporadically found throughout the MHI, but abundant in the NWHI. Dietary overlap was high between gray reef and sandbar sharks, and between sandbar and Galapagos sharks. Tiger sharks had low dietary overlap with all other species, except for large Gala- pagos sharks. The data analyzed in our study support the hypothesis that interspecific competition influences the distribution of carcharhinid sharks throughout the Hawaiian Archipelago.

[1]  W. D. Mcelroy,et al.  Food habits and ontogenetic changes in the diet of the sandbar shark, Carcharhinus plumbeus, in Hawaii , 2006, Environmental Biology of Fishes.

[2]  J. Carlson,et al.  Foraging ecology of the early life stages of four sympatric shark species , 2004 .

[3]  I. Potter,et al.  Comparisons between the diets of four abundant species of elasmobranchs in a subtropical embayment: implications for resource partitioning , 2004 .

[4]  C. Lowe,et al.  Ontogenetic dietary shifts and feeding behavior of the tiger shark, Galeocerdo cuvier, in Hawaiian waters , 1996, Environmental Biology of Fishes.

[5]  C. Lowe,et al.  Biology of the Galapagos shark,Carcharhinus galapagensis, in Hawai'i , 1996, Environmental Biology of Fishes.

[6]  R. Elst.  A proliferation of small sharks in the shore-based Natal sport fishery , 1979, Environmental Biology of Fishes.

[7]  H..  Depth , capture time , and hooked longevity of longline-caught pelagic fish : Timing bites of fish with chips , 2004 .

[8]  Christopher G. Lowe,et al.  Diel movement patterns of the Hawaiian stingray, Dasyatis lata: implications for ecological interactions between sympatric elasmobranch species , 2003 .

[9]  Alan M. Friedlander,et al.  Contrasts in density, size, and biomass of reef fishes between the northwestern and the main Hawaiian islands: the effects of fishing down apex predators , 2002 .

[10]  A. Finstad,et al.  Niche segregation between Arctic char (Salvelinus alpinus) and brown trout (Salmo trutta): an experimental study of mechanisms , 2002 .

[11]  W. T. Stobo,et al.  Shark‐inflicted mortality on a population of harbour seals (Phoca vitulina) at Sable Island, Nova Scotia , 2000 .

[12]  N. Dulvy,et al.  Fishery Stability, Local Extinctions, and Shifts in Community Structure in Skates , 2000 .

[13]  E. Cortés.  Standardized diet compositions and trophic levels of sharks , 1999 .

[14]  Christopher G. Lowe,et al.  Movements of tiger sharks (Galeocerdo cuvier) in coastal Hawaiian waters , 1999 .

[15]  Christopher G. Lowe,et al.  Distribution, reproduction and diet of the gray reef shark Carcharhinus amblyrhynchos in Hawaii , 1997 .

[16]  E. Cortés.  A critical review of methods of studying fish feeding based on analysis of stomach contents: application to elasmobranch fishes , 1997 .

[17]  C. Lowe,et al.  Shark Records from Longline Fishing Programs in Hawai'i with Comments on Pacific Ocean Distributions , 1996 .

[18]  J. Ellis,et al.  The Comparative Feeding Ecology of Six Species of Shark and Four Species of Ray (Elasmobranchii) In The North-East Atlantic , 1996, Journal of the Marine Biological Association of the United Kingdom.

[19]  J. Randall.  Shore fishes of Hawaii , 1996 .

[20]  Christopher G. Lowe,et al.  A Review of Shark Control in Hawaii with Recommendations for Future Research , 1994 .

[21]  B. Jonsson,et al.  Resource partitioning and niche shift in Arctic charr Salvelinus alpinus and brown trout Salmo trutta , 1991 .

[22]  R. H. Johnson.  Sharks of Tropical and Temperate Seas , 1991 .

[23]  John A. Wiens,et al.  The Ecology Of Bird Communities , 1989 .

[24]  D. R. Nelson,et al.  Patterns of movement and grouping of gray reef, Carcharhinus amblyrhynchos at Enewetak, Marshall Islands , 1986 .

[25]  R. Langton.  DIET OVERLAP B,ETWEEN ATLANTIC COD, GADUS MORHUA, SILVER HAKE, MERLUCCIUS BILINEARIS, AND FIFTEEN OTHER NORTHWEST ATLANTIC FINFISH , 1982 .

[26]  M. Hixon.  COMPETITIVE INTERACTIONS BETWEEN CALIFORNIA REEF FISHES OF THE GENUS EMBIOTOCA , 1980 .

[27]  Daniel Simberloff,et al.  The Assembly of Species Communities: Chance or Competition? , 1979 .

[28]  E. Pianka.  The structure of lizard communities , 1973 .

[29]  Robert K. Colwell,et al.  On the Measurement of Niche Breadth and Overlap. , 1971, Ecology.

[30]  A. Rand,et al.  Competition in tropical stream fishes : support for the competitive exclusion principle , 1971 .

[31]  R. Wass.  A comparative study of the life history: distribution and ecology of the sandbar shark and the gray reef shark in Hawaii , 1971 .