Occurrences of Steelhead Trout (Oncorhynchus mykiss) in southern California, 1994-2018
Observations of federally endangered Southern Steelhead Trout (Oncorhynchus mykiss) were compiled for the southern California Distinct Population Segment (DPS) that extends approximately 500 kilometers from the Santa Maria River (Santa Barbara County) south to the Mexican border. Existing monitorin...
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| Format: | Article |
| Language: | English |
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California Department of Fish and Wildlife
2020-01-01
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| Series: | California Fish and Wildlife Journal |
| Subjects: | |
| Online Access: | https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=175916&inline |
| _version_ | 1797783630715551744 |
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| author | Rosi Dagit Michael T. Booth Mauricio Gomez Timothy Hovey Steve Howard Scott D. Lewis Sandra Jacobson Mary Larson Dan McCanne Timothy H. Robinson |
| author_facet | Rosi Dagit Michael T. Booth Mauricio Gomez Timothy Hovey Steve Howard Scott D. Lewis Sandra Jacobson Mary Larson Dan McCanne Timothy H. Robinson |
| author_sort | Rosi Dagit |
| collection | DOAJ |
| description | Observations of federally endangered Southern Steelhead Trout (Oncorhynchus mykiss) were compiled for the southern California Distinct Population Segment (DPS) that extends approximately 500 kilometers from the Santa Maria
River (Santa Barbara County) south to the Mexican border. Existing monitoring
programs and anecdotal observations documented 177 adult Steelhead in the past 25 years. The level of monitoring effort and technology used varied by watershed and year. Thus, the low numbers of adult Steelhead observed during the past 25 years provides relative abundance and distribution documentation of occurrences but likely underestimates the abundance of adult Steelhead throughout the DPS. The patchy distribution observed suggests that fish are opportunistically entering creeks and river mouths based on available hydrologic passage opportunities associated with higher rainfall years. Given the extremely low numbers of anadromous adults, long recovery timeline, future uncertainty with respect to climate change, and a multitude of anthropogenic factors, additional conservation actions including state and federal protection of resident O. mykiss are recommended to increase the likelihood of the continued existence of the species within the DPS. Additional focused monitoring, research, and implementation of recovery actions are needed to expand our knowledge of southern California Steelhead distribution and abundance. |
| first_indexed | 2024-03-13T00:28:37Z |
| format | Article |
| id | doaj.art-0301d942a0cd463c92f7daa042d17a6a |
| institution | Directory Open Access Journal |
| issn | 2689-419X 2689-4203 |
| language | English |
| last_indexed | 2024-03-13T00:28:37Z |
| publishDate | 2020-01-01 |
| publisher | California Department of Fish and Wildlife |
| record_format | Article |
| series | California Fish and Wildlife Journal |
| spelling | doaj.art-0301d942a0cd463c92f7daa042d17a6a2023-07-10T21:48:03ZengCalifornia Department of Fish and WildlifeCalifornia Fish and Wildlife Journal2689-419X2689-42032020-01-0110613910.51492/cfwj.106.4Occurrences of Steelhead Trout (Oncorhynchus mykiss) in southern California, 1994-2018Rosi Dagit0https://orcid.org/0000-0001-8435-7178Michael T. Booth1Mauricio Gomez2Timothy Hovey3Steve Howard4Scott D. Lewis5Sandra Jacobson6https://orcid.org/0000-0001-6839-6900Mary Larson7Dan McCanne8Timothy H. Robinson9Resource Conservation District of the Santa Monica MountainsUnited Water Conservation District and University of CincinnatiSouth Coast Habitat RestorationCalifornia Department of Fish and WildlifeUnited Water Conservation District and Rincon Consultants, Inc.Casitas Municipal Water DistrictCalifornia TroutCalifornia Department of Fish and WildlifeCalifornia Department of Fish and WildlifeCachuma Operations Management BoardObservations of federally endangered Southern Steelhead Trout (Oncorhynchus mykiss) were compiled for the southern California Distinct Population Segment (DPS) that extends approximately 500 kilometers from the Santa Maria River (Santa Barbara County) south to the Mexican border. Existing monitoring programs and anecdotal observations documented 177 adult Steelhead in the past 25 years. The level of monitoring effort and technology used varied by watershed and year. Thus, the low numbers of adult Steelhead observed during the past 25 years provides relative abundance and distribution documentation of occurrences but likely underestimates the abundance of adult Steelhead throughout the DPS. The patchy distribution observed suggests that fish are opportunistically entering creeks and river mouths based on available hydrologic passage opportunities associated with higher rainfall years. Given the extremely low numbers of anadromous adults, long recovery timeline, future uncertainty with respect to climate change, and a multitude of anthropogenic factors, additional conservation actions including state and federal protection of resident O. mykiss are recommended to increase the likelihood of the continued existence of the species within the DPS. Additional focused monitoring, research, and implementation of recovery actions are needed to expand our knowledge of southern California Steelhead distribution and abundance.https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=175916&inlineanadromous adultsrainbow troutsouthern californiasouthern steelhead |
| spellingShingle | Rosi Dagit Michael T. Booth Mauricio Gomez Timothy Hovey Steve Howard Scott D. Lewis Sandra Jacobson Mary Larson Dan McCanne Timothy H. Robinson Occurrences of Steelhead Trout (Oncorhynchus mykiss) in southern California, 1994-2018 California Fish and Wildlife Journal anadromous adults rainbow trout southern california southern steelhead |
| title | Occurrences of Steelhead Trout (Oncorhynchus mykiss) in southern California, 1994-2018 |
| title_full | Occurrences of Steelhead Trout (Oncorhynchus mykiss) in southern California, 1994-2018 |
| title_fullStr | Occurrences of Steelhead Trout (Oncorhynchus mykiss) in southern California, 1994-2018 |
| title_full_unstemmed | Occurrences of Steelhead Trout (Oncorhynchus mykiss) in southern California, 1994-2018 |
| title_short | Occurrences of Steelhead Trout (Oncorhynchus mykiss) in southern California, 1994-2018 |
| title_sort | occurrences of steelhead trout oncorhynchus mykiss in southern california 1994 2018 |
| topic | anadromous adults rainbow trout southern california southern steelhead |
| url | https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=175916&inline |
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