The relative importance of introduced fishes, habitat characteristics, and land use for endemic shrimp occurrence in brackish anchialine pool ecosystems
Marrack L, Beavers S, O'Grady P. 2015. The relative importance of introduced fishes, habitat characteristics, and land use for endemic shrimp occurrence in brackish anchialine pool ecosystems. Hydrobiologia. 758:107–122
Abstract Anchialine ecosystems are groundwaterfed brackish coastal habitats that contain high percentages of endemic fauna and are at risk from anthropogenic stressors, introduced species, and sea level rise. Data on endemic species distribution, habitat condition, and species/habitat interactions in this ecosystem are scarce across large spatial scales. This study offers the most thorough regional perspective on anchialine pool habitat characteristics along the western and southern coastlines of the island of Hawaii since the 1970s. Daytime surveys of 398 anchialine pools documented the widespread distribution of two dominant endemic shrimp Halocaridina rubra and Metabetaeus lohena in a wide range of habitats. Introduced fishes (tilapia, poeciliids) were present in about 25% of pools. Generalized additive models were used to determine the relationship between shrimp occurrence and pool characteristics, invasive species, water properties, and land use. Introduced fishes had a strong negative effect on the occurrence of H. rubra and M. lohena. High benthic silt cover and adjacent development also had significant negative relationships with shrimp occurrence. Our results indicate that conservation efforts should include controlling introduced fishes, preventing new introductions, minimizing siltation, and protecting groundwater resources and low-lying coastal areas.
- Type
- Journal Article
- Authors
- Marrack, Lisa; Beavers, Sallie; O'Grady, Patrick
- Units
- KAHO
- Keywords
- Aytid shrimp, Groundwater ecosystem, Halocaridina rubra, land use, Metabetaeus lohena, Poeciliids, Tilapia