habitats and sensitive wildlife species of the ventura river watershed · 2010. 5. 25. ·...
TRANSCRIPT
Habitats and Sensitive Wildlife Species of the Ventura River
Watershed
Laura Riege, Sr. Project Ecologist
Ventura River Watershed UMay 13, 2010
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Introduction
• Watershed overview from a wildlife habitat perspective
• Overview of the sensitive wildlife species in the watershed
• Four listed species that are frequently impacted by projects
• Invasive species threatening the watershed
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Overview: Ventura River Watershed
Ventura River Preserve
Ventura River Confluence Reserve
Ilvento Preserve
Ojai Meadows Preserve
Total Watershed area = 223 square miles
Nearly half are in the National Forest
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Vegetation Communities• Wetland Habitats
– Lacustrine– Riverine– Palustrine– Estuarine– MarineRiparian
• Upland Habitats– Grassland– Scrub– Chaparral– Woodland– Sand Dunes
Lacustrine
Marine & Sand Dune
Palustrine & Grassland
Riverine
Scrub and Chaparral
Estuarine
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Land Use and Vegetation Types
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Sensitive Species in the Watershed
• 3 fish• 2 amphibians• 5 reptiles• 29 birds• 2 mammals
Many others are “watch list”
• 7 endangered• 3 threatened• 22 CA species of
special concern• 4 CA fully protected• 4 other protections
(e.g., state or federal forest service)
40 sensitive wildlife species
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Protection Under ESA and CESAFederal Endangered Species Act:
– Federal ESA prohibits the “take” of any threatened or endangered animals and protects their habitat
– Take is defined as “to harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect or attempt to engage in any such conduct”
– “Harm” is defined as “an act which actually kills or injures wildlife.” Harm includes significant habitat modification or degradation
– Section 7 – Federal Actions– Section 10 – Non-federal Actions
Habitat Conservation Plan (HCP)
California ESA:– Fish and Game Code prohibits "take" of any species that the commission
determines to be an endangered species or a threatened species – Take is defined as "hunt, pursue, catch, capture, or kill, or attempt to hunt,
pursue, catch, capture, or kill" – Fully Protected species may not be taken or possessed at any time
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T&E Species: Estuarine and Sand Dune
• Tidewater goby• California least tern• Western snowy plover• Southern steelhead• California brown
pelican – delisted!CA Fully Protected
species
Photo Courtesy California State Parks
Photo by Steve Howard
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T&E Species: Riverine/Riparian
• Southern Steelhead• California red-legged
frog• Least Bell’s vireo• Bank swallow• Southwestern willow
flycatcher• Western yellow-billed
cuckoo
Photo by Marcel GahbauerPhoto by Nicky Davis
Photo by Kylie Fischer
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T&E Species: Upland
• California Condor• American peregrine
falcon – delisted!CA Fully Protected
species
Photo by Francois Gohier/Auscape Intl.
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Southern Steelhead
• Steelhead are the ocean-going (anadromous) form of rainbow trout
• Juveniles spend 1-3 years in freshwater to rear– Require pool or riffle habitat, optimally less than
20°C/68°F with good dissolved oxygen– May rear in the lagoon/estuary– Smolts require adequate flows to migrate to ocean
• Adults spend 1-2 years in the ocean before returning to the stream to spawn– Usually migrate in storm events with good flows– Require good gravels to lay eggs (spawn) with
clear water and good dissolved oxygen
Federally-listed Endangered/CA Species of Special Concern
Photo by John Southwick
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Steelhead Spawning Habitat
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Steelhead Rearing Habitat
Rearing habitat is
the limiting factor for
steelhead in the Ventura
River
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California Red-legged Frog
• In a wide range of aquatic habitats: creeks, streams, and ponds that have perennial or near-perennial standing water
• Breeds from November through March• Breeding sites: deep pools or backwaters within
streams, ponds, marshes, dune ponds, lagoons, and artificial impoundments
• During the summer adults may move to forested sections of slow streams with undercut banks and exposed root masses
• Frogs also occur in upland habitat; recorded moving over two miles from nonbreeding to breeding sites
Federally-listed Threatened/ CA Species of Special Concern
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Suitable Habitat and Recent Sightings of California Red-legged Frog
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Least Bell’s vireo
• Structurally diverse woodlands in riparian areas– Dense cover within 2 meters of the ground for
nesting – Dense, stratified canopy for foraging– Well-developed overstory (willow, cottonwood,
sycamores) with a dense shrub understory– Nests in shrubs between 5 – 10 years old
• Prey on a variety of insects including beetles, bugs, grasshoppers, caterpillars, and moths
• Breeding season is April 1 through August 31
Federally- and State-listed Endangered
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Least Bell’s Vireo: Suitable Habitat
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Tidewater Goby
• Inhabits coastal brackish water habitats of estuaries and lagoons
• Favors calm conditions when lagoons are cut-off from the ocean by beach sandbars
• Low-salinity conditions and minimal water currents
• Bottom dwellers and are: found at water depths of less than 3 feet
• Requires fresh unconsolidated sand for reproduction
• Life spans are approximately 1 year
Federally-listed Endangered/CA Species of Special Concern
Photo courtesy USFWS
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Invasive Species
Ventura River Streamteam
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Invasive SpeciesAn "invasive species" is
1) non-native (or alien) to the ecosystem 2) whose introduction causes … economic or environmental harm, or
harm to human health
Small subset of exotic, non-native, alien species are invasive– May be native, even endangered, in one place and invasive in
another
U.S. spends ~$120 billion annually on invasive species
Invasives impact approximately half of all federally-listed species;40% of all animal extinctions due in part to invasive species
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Problems caused by invasive species
• Prey on native species– bullfrogs, green sunfish
• Compete with native species – Arundo
• Spread parasites/diseases– West Nile Virus
• Change physical conditions – zebra mussels, crayfish
• Harm to infrastructure and recreation– quagga mussels
Star Thistle
Bullfrog (left) and Red-legged Frog (right)
New Zealand Mudsnail
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Giant Reed Impacts to Riparian/Riverine Habitat
Outcompete native riparian plants– Inadequate habitat for nesting birds– Does not support insects and other prey for foraging
birds and wildlife– Does not provide food for wildlife– Does not provide overhanging cover and instream
cover for fish
Form dense, pure stands – Block fish migration– Increased flood risk– Highly flammable
High water demand reduces instream habitat for fish and amphibians
Giant Reed
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Aquatic Invasive SpeciesNew Zealand MudsnailSize: a grain of sand to 1/8 inch in lengthColor: black or brown• Reproduce clonally to very high
densities• Compete with native invertebrates and
reduce food resources for fish• Small and sticky, spread through
hatcheries and as “hitchhikers” on gear and clothing
Quagga and Zebra MusselsSize: fingernail-sized but can grow up to 2
inchesQuagga: black, cream, or white bandsZebra: alternating dark and light stripes• Damage ecosystems and clog pipes
and other infrastructure• Spread through water transfers and
trailered boats
Color variation in Zebra and Quagga mussels.
New Zealand Mudsnail
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Invasive Species: General Best Practices• Do not transfer water, mud, plants or
seeds from one stream or study area to another– Inspect boats, fishing gear, boots and clothes– Quarantine gear, dry, or freeze– Remove visible snails with a stiff brush and follow
with rinsing• Do not plant invasive species• Never release water or organisms from a
fish tank or water garden• Comply with boat washes, inspections,
Casitas quarantine
Quagga mussels can survive three to five days out of water depending upon temperature and humidity in
summer, longer in the winter - up to 30 days
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Questions?