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Impacts of the Russian RiverSandbar on Wildlife
Copyright © 2002-2008 Kenneth & Gabrielle Adelman, California Coastal Records Projectwww.Californiacoastline.org
Harbor Seals
Jamie Hall Photo
Jenner Is a Major North Coast Harbor Seal Haulout
• At molt, it is the largest between Drake’s
Estero and the mouth of the Eel River
• State seal census shows it has been important
California haulout since the 1980s
Jenner Is Sonoma County’s Major Haulout
Regional Census Sites
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Ave
rage
Jenner is also one of the most intensively studied haulouts on
the West Coast• State summer census began in 1982
• Monthly counts begin in 1988
• Elinor Twohy’s Daily Counts since Linda Hansen’s study of harbor ecology, completed in 1993
• Regional Census since 1998
• So we know trends over years and seasons
Elinor Twohy’s Daily Seal Census RevealsTwo Types of Seasonal Patterns
Joe Mortenson Photo
Haulout With Winter Maximum in 1994Original Pattern Observed in 1990s
1994 Winter Haulout
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12/9/93 1/28/94 3/19/94 5/8/94 6/27/94 8/16/94 10/5/94 11/24/94 1/13/95 3/4/95
Tota
l S
ea
ls
WinterStorm
ShelterPupping Molting Dispersal,
River Often Barred
Original Seal Annual Cycle Components
1995 Haulout, Winter MaximumShowing Similar Pattern
1995 Haulout
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700
11/23/1990 1/12/1991 3/3/1991 4/22/1991 6/11/1991 7/31/1991 9/19/1991 11/8/1991 12/28/1991 2/16/1992
Tot
al C
ount
Jenner Seals Came to Avoid or Flee R-1, A Maturing Elephant Seal Bull
Jamie Hall Photo
Ultimately, R-1 Devastated Jenner Haulout
Lisa Hug Photo
2006 Haulout, with R-1 PresentWinter Haulout Disappears
2006 Total Jenner Seals
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11/6/05 12/26/05 2/14/06 4/5/06 5/25/06 7/14/06 9/2/06 10/22/06 12/11/06 1/30/07
HauloutVanishes
In 2007 R-1 Lingered into Breeding Season Haulout Numbers Were Reduced Save for Molt
2007 Total Jenner Seals
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12/11/06 1/30/07 3/21/07 5/10/07 6/29/07 8/18/07 10/7/07 11/26/07 1/15/08 3/5/08
MoltRemains
Decline in Jenner HauloutYearly Average
Jenner Seals
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1992 1994 1996 1998 2000 2002 2004 2006 2008
Year
Ave
rage
Sea
ls
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1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009
Mean S
eals
Seals
Pups
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1403/
20/0
9
3/27
/09
4/3/
09
4/10
/09
4/17
/09
4/24
/09
5/1/
09
5/8/
09
5/15
/09
5/22
/09
5/29
/09
SealsPups
In Fall, Seal Counts Drop at the Time When the Sandbar Tends to Form
2007 Total Jenner Seals
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12/11/06 1/30/07 3/21/07 5/10/07 6/29/07 8/18/07 10/7/07 11/26/07 1/15/08 3/5/08
Bar Likely to Form
Sandbar Affects Harbor Seal Colony Strongly In Fall
• Sandbar indicated by bar in graphs
• Seals often abandon Jenner when bar forms
• Quick return after breach
Possible Results of Sandbar Earlier in the Year
• We know a single source of disturbance like R-1 can wipe out a haulout
• Similar case of haulout elimination in part as a result of early morning walkers and other factors at Strawberry Point in Marin County
• Data shows that sandbar consistently reduces Harbor Seal haulout population
• Prolonged sandbar without breaching may reduce or eliminate this significant Harbor Seal haulout in molt
Jenner is Also for the Birds
Kevin O’Connor Photo
Hundreds of Birds May Rest on the Bar
• Rest is vital not just for seals and people, but also for birds
• Many species of coastal birds congregate on the Russian River Spits
• Some come from our local colonies, others from distant rookeries
• Birds are put to flight by people walking across the bar and often abandon the area
Jenner Sea Mammals and Sea Birds Enjoy Legal Protections
Kevin O’Connor Photo
Brown Pelicans at Jenner are a Bird of Special Concern under the Endangered Species Act and Heerman’s Gulls are
protected under the Migratory Bird Treaty
Kevin O’Connor Photo
Photo by George Zastrow
Marine Mammal Protection Act Covers Seals, Sea Lions and Whales
North Central Coast Marine Life
Protection Plan is Being Finalized
Marine Life Protection Act Provides General Protection
• Provisionally the Outer Mouth will be a State Marine Conservation Area
• And the Estuary will be a State Marine Reserve
Extension of the Gulf of the Farallones National Marine Sanctuary
• GFNMS likely to be
extended northward shortly,
bringing more protections to
Jenner and the coast
• Thus Jenner may be protected
by many laws and agencies,
just like Bolinas Lagoon
Many Other Species Will Affected by Closure
• The Estuary is a nursery for dungeness crabs
• How will they and other species be affected?
In Summary, the River Mouth Is and Will Be Protected
• The Migratory Bird Treaty
• The Marine Mammal Protection Act
• Marine Life Protection Act
• Extension of the Gulf of the Farallones National Marine Sanctuary
But how do these bear on the Biological Opinion?
Why Not Integrated Management?
• Manage for all species, not just two
• Consider the breadth of consequences
• Take holistic approach
• There are many stakeholders at the mouth of the Russian River
Finally Remember
The Jenner Seals are Ambassadors for the Marine Environment
The seals link children,
visitors, all of us, to the estuary and to the sea
Kevin O’Connor Photo
Jenner Seals
Ambassadors to the Marine Environment • Harbor Seals provide a connection for visitors to the
otherwise inaccessible ocean environment
• Beach, estuary and Route 1 overlook provide public exceptional visual access to the river/ocean interface
• The overlook is a destination for thousands of travelers along the Sonoma County coast who stop just to see the Harbor Seals
State Park
Seal Watchers
Educate the Public while Protecting
the Seals.
Stewards of the Coast and Redwoods supports the State Park Volunteer in Parks Programs. Seal Watch was their first program and Seal Watchers have been protecting the Harbor Seal colony since 1985.
When we try to pick anything out by itself, we find it hitched to
everything else in the universe. -John Muir
Kevin O’Connor Photo
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