General Impact
In Hawaii bluestripe snapper share the same habitat with native fishes such as goatfish Mulloidichthys sp. (Friedlander et al. 2002). This may result in competition for habitat use and food sources. Evidence has been documented which suggests that bluestripe snapper may displace native fish from important refuge habitat. Competition for shelter appears to be the most significant impact detected, with the dominant L. kasmira able to displace native fish from areas of the reef which offer protection (Schumacher and Parrish 2005). It has also been argued that the deliberate introduction of L. kasmira in Hawaii has lead to the replacement of many other locally important catch species (Russo 1994; FAO 2001). However this remains a controversial topic and more research investigating the ecological niche of L. kasmira is needed. Disease transmission to native fish may also occur (Work et al. 2003).
Location Specific Impacts:Kaua`i Is. (United States (USA)) Competition: In a study by DeFelice and Parrish (2003) at Hanalei Bay overall dietary overlap between L. kasmira and other fish species was found to be relatively low and there was no indication that food resources were limiting in this habitat. The stomachs of 15 L. kasmira (10.0–17.9cm SL) were found to contain mainly small caridean shrimps, especially Ogyrididae. The diet of L. kasmira overlapped somewhat with that of Albula sp. and less so with that of Mulloidichthys pflugeri. L. kasmira and Albula sp. had stomatopods, ogyridid shrimp, and portunid crabs in common in their diet, and L. kasmira and M. pflugeri shared stomatopods, penaeid shrimp, portunid crabs, and small cryptic fishes. Maui Is. (United States (USA)) Competition Oahu Is. (United States (USA)) Competition: There seems to be no significant overlap in diet to support intense competition for food between L. kasmira and locally important fish species such as Parupeneus porphyreus or Mulloidichthys jlavolineatus. The ecological niche of L. kasmira is still not completely understood, and more information is needed to conclusively determine why it has increased greatly in abundance since 1958 while other fish species important to the local fishermen have declined (Russo 1994). Economic/Livelihoods: Local fishermen suspect that L. kasmira may eat the juveniles of locally important fish species as 40% of its diet is fish. However, there is little conclusive evidence to support this. Oda and Parrish (1982) found some evidence of holocentrid fish (genus Myripristis) remains in the guts of L. kasmira but not in sufficient quantity to justify its classification as a major fish predator of locally important fishes (Russo 1994). Predation: 40% of the diet of L. kasmira is fish (Russo 1994). Hawaii (United States (USA)) Competition: Taape may compete with native fish through habitat use, diet, predation on larvae, or disease transmission to native fish (Work et al. 2003). Although no direct competition between native fish and taape has been documented taape do share the same habitat with native fish and closely associate with certain native fish such as goatfish Mulloidichthys sp. (Friedlander et al. 2002).Schumacher and Parrish (2005) found that habitat use patterns of the yellowtail goatfish (Mulloidichthys vanicolensis) are most similar to those of L. kasmira. Both species are primarily found low in the water column and closely associated with areas of vertical relief. Individual M. vanicolensis were found higher in the water column when L. kasmira were present, but the latter were not similarly affected by M. vanicolensis. This finding suggests competition for shelter does occur between the two fish and that the dominant L. kasmira displaces M. vanicolensis from areas of the reef which offer protection. Disease transmission: In Hawaii, taape have been found infected with bacteria and an apicomplexan protozoan compatible with a coccidian. Disease transmission may negatively impact native marine fishes that are closely associated with taape (Work et al. 2003).
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