Steelhead in the Monterey Bay Region
A watershed-related issue examined by the ENVS 560/L Watershed Systems class at CSUMB.
Contents
- 1 Summary
- 2 Steelhead Basics
- 3 Steelhead Management Challenges
- 4 Habitat in the Monterey Bay Region
- 5 Management Challenges in the Monterey Bay Region
- 6 Conservation and Restoration Efforts
- 7 Resources at stake
- 8 Stakeholders
- 9 Laws, policies, & regulations
- 10 Systems
- 11 Science
- 12 References
- 13 Links
- 14 Disclaimer
Summary
Steelhead present unique management challenges compared to other salmonids due to their life history plasticity. These management challenges are compounded because the Monterey Bay Region is split into two Distinct Population Segments (DPS), the South-Central California Coast Steelhead and the Central California Coast Steelhead. A DPS is a population of species that is discrete from other populations and reproductively isolated from other populations. [1] Steelhead in the Monterey Bay Region face difficult environmental conditions because of the unique topography of the area, and proximity to the southern limit of the species range. Both DPS in the Monterey Bay Region are currently listed as threatened under the Endangered Species Act (ESA).
Steelhead Basics
Steelhead (Oncorhynchus mykiss) in the Monterey Bay Region are listed as "Threatened" under the Endangered Species Act (ESA) and occupy many rivers and streams flowing into the Monterey Bay. O. mykiss are distinct among salmonid species because the are both facultativly anadromous and iteroparous. Anadromous fish are those that spend most of their life in the ocean and spawn in freshwater. Iteroparous fish are that can reproduce multiple times in their life. Typically salmonids are semelparous, meaning they only reproduce once before dying. O. mykiss also have populations which reside in freshwater and are called rainbow trout. [3].
Steelhead Management Challenges
There is great variability in age of Steelhead emigration and return age, along with the probability of repeat spawning. There are 32 identified possible life history trajectories for Steelhead which presents a great challenge for managing the species [4]. Changes in freshwater conditions due to water management or climate change may alter demographic rates along with the current life history trajectories, sending fish on alternative trajectories with radically different demographic results [3].
Habitat in the Monterey Bay Region
The Monterey Bay, located on the Central Coast of California, is the centerpiece of the Monterey Bay National Marine Sanctuary. MAP. Steelhead in the Monerey Bay Region are of particular interest for several reasons. These fish are near the southern limit of the species range, and face environmental conditions quite distinct from Northern California populations. The Mediterranean climate of the Monterey Bay Region results in temperatures that are typically higher than those found to the north, with mild winters and productive high-flow springs supporting the highest growth rates [5]. In contrast, rainfall and stream-flow are low during the summer and fall, limiting growth rates. The small coastal streams of the Monterey Bay Region frequently feature sand-bar closed estuaries during low-flow periods that may provide ideal nursery habitat for smolts [6] [5], but also constrain potential emigration and return dates to when stream-flow is high enough to breach the sandbar [3].
Management Challenges in the Monterey Bay Region
The Monterey Bay Region is comprised of two DPSs, designated by two Environmentally Significant Units (ESU). The Central California Coast Section extends from the Russian River (inclusive)south to Aptos Creek (inclusive), and the South Central California Coast Section extends south from the Pajaro River (inclusive) to the Santa Maria River (exclusive), effectively splitting the Monterey Bay in half. Both ESUs are currently designated as "Threatened" under the ESA, and both DPSs are currently designated as "Critical Habitat" for Steelhead [7].
Conservation and Restoration Efforts
The National Oceanic and Atmospheric Administration (NOAA), National Marine Fisheries Service (NMFS), Southwest Fisheries Science Center (SWFSC) has been working closely with the Monterey Bay Salmon and Trout Project (MBSTP) on the restoration of Steelhead populations in the Monterey Bay Region. NMFS and MBSTP operate the Kingfisher Flat Conservation Hatchery outside Davenport, CA, in an effort to restore Steelhead populations and maintain the genetic diversity of local populations. Returning adult Steelhead are captured and spawned with both wild returning adults and with captive broodstock adults to ensure greatest possible genetic diversity. Yearlings are transported and released into rivers and streams in the Monterey Bay Region each fall.
Resources at stake
Recreational and commercial fishing, diversity, ecosystem, marine derived nutrients
Stakeholders
Recreational and commercial fishermen, NOAA/NMFS, CDF&G, MBSTP, CalFish, FishNet 4C, MCWRA, SWRCB
Laws, policies, & regulations
ESA, NOAA Action Plans,
Systems
Marine/Terrestrial interaction
Science
NOAA/NMFS/SWFSC, MBSTP, FISHBIO
References
- ↑ Environmental Commons, Date accessed April 10th 2012 http://environmentalcommons.org/hatchery-fish.html
- ↑ UC Davis Salmon and Steelhead life history
- ↑ 3.0 3.1 3.2 Satterthwaite WH, Beaks MP, Collins EM, Swank DR, Merz JE, Titus RG, Sogard SM, Mangel M. 2009. Steelhead life history on California's Central Coast: insights from a state-dependent model. Transactions of the American Fisheries Society 138:532-548.
- ↑ Thorpe JE. 2007. Maturation responses of salmonids to changing developmental opportunities. Marine Ecology Progress Series 335:285-288
- ↑ 5.0 5.1 Hayes SA, Bond MH, Hanson CV, Freund EV, Smith JJ, Anderson EC, Ammann AJ, MacFarlane RB. 2008. Steelhead growth in a small central California watershed: upstream and estuarine rearing patterns. Transactions of the American Fisheries Society 137:114-128.
- ↑ Bond MH, Hayes SA, Hanson CV, MacFarlane RB. 2008. Marine survival of steelhead (Oncorhynchus mykiss) enhanced by a seasonally closed estuary. Canadian Journal of Fisheries and Aquatic Sciences 65:2242-2252.
- ↑ Steelhead ESA Listings http:://http://www.nwr.noaa.gov/ESA-Salmon-Listings/Salmon-Populations/Steelhead/Index.cfm
Links
- National Oceanic and Atmospheric Administration (NOAA)
- Steelhead ESA Listings
- National Oceanic and Atmospheric Administration, National Marine Fisheries Service (NOAA/NMFS)
- National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Southwest Fisheries Science Center (NOAA/NMFS/SWFSC)
- National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Northwest Fisheries Science Center (NOAA/NMFS/NWFSC)
- Monterey Bay Salmon and Trout Project (MBSTP)
- FishNet 4C
- FISHBIO
- CalFish
- California Department of Fish and Game (CDF&G)
- Monterey County Water Resources Agency (MCWRA)
- State Water Resources Control Board, Central Coast Section (SWRCB/CCS)
Disclaimer
This page may contain student work completed as part of assigned coursework. It may not be accurate. It does not necessary reflect the opinion or policy of CSUMB, its staff, or students.
