Monitoring the distribution and abundance of native gobies (oopu) in Waikolu and Pelekunu streams on the island of Molokai
Brasher AM. 1996. Monitoring the distribution and abundance of native gobies (oopu) in Waikolu and Pelekunu streams on the island of Molokai. Technical Report 113. Cooperative National Park Resources Studies Unit, University of Hawai`i at Manoa
Over a 2-year period, two streams on the Island of Molokai were surveyed to determine distribution and abundance of 3 native freshwater goby species: Awaous guamensis, Sicyopterus stimpsoni and Lentipes concolor. One stream (Waikolu) had a series of water diversions in its upper reaches, while the other (Pelekunu) was free-flowing. There was a high degree of overlap in the longitudinal distribution of the three species, probably due to the relatively low gradient of the stream channels and to lack of any major waterfalls in the lower and mid-reaches. A. guamensis was more abundant in Pelekunu Stream, while densities of S. stimpsoni and L. concolor were not significantly different between streams. No A. guamensis were recorded in the section of Waikolu Stream above the diversions. At comparable stations below the diversions, there was no significant difference in S. stimpsoni abundance between the two streams, but at comparable stations in and above the diversions, Pelekunu Stream had significantly more S. stimpsoni. Similarly, L. concolor was more abundant at comparable stations below the diversions in Waikolu Stream, but significantly less abundant than in Pelekunu Stream at comparable stations above the diversion. The lower number of gobies observed at the mid- and upper reaches of Waikolu Stream was most likely a result of decreased flow and periodic dewatering of the stream section below the upper dam, reducing available habitat and inhibiting upstream migration.
- Type
- Published Report
- Authors
- Brasher, Anne
- Date of Issue
- 1996-02
- Publisher
- Cooperative National Park Resources Studies Unit, University of Hawai`i at Manoa
- Units
- KALA
- Keywords
- `o`opu, Animal Studies, Distribution, goby, Hawaii, Molokai, oopu, Pelekunu, Population, Stream, Waikolu