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Published byClarissa Underwood Modified over 9 years ago
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In Favor of a Year-Round Rope Carol Archibald, PhD Member, La Jolla Friends of the Seals
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Site Fidelity Harbor seals stick to familiar resting spots or haul out sites, usually coastal Harbor seals stick to familiar resting spots or haul out sites, usually coastal La Jolla rookery’s historic haul out site documented from late 1887 map La Jolla rookery’s historic haul out site documented from late 1887 map Seals may have used La Jolla site for centuries Seals may have used La Jolla site for centuries
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Importance of Beach for Seals Seals need beach to survive Seals need beach to survive –For resting, re-oxygenation, thermal regulation, molting –For resting, re-oxygenation, thermal regulation, molting –Birthing, nursing, raising of pups This beach is a major haul out site for all Southern CA seals This beach is a major haul out site for all Southern CA seals Only birthing area south of Point Magu (north of LA) Only birthing area south of Point Magu (north of LA)
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Necessity for haul-out in harbor seals. Brasseur 1996 Immediately after captive seals were intentionally deprived of being able to haul out, they hauled out more to compensate for the deprivation, especially during daylight hours.
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Numerous studies confirm disturbances from human activities impact harbor seal haul-out behavior Renouf 1981; Schneider and Payne 1983; Terhune and Almon 1983; Allen 1984; Stewart 1984; Suryan and Harvey 1999; Mortenson 2000). Numerous studies confirm disturbances from human activities impact harbor seal haul-out behavior Renouf 1981; Schneider and Payne 1983; Terhune and Almon 1983; Allen 1984; Stewart 1984; Suryan and Harvey 1999; Mortenson 2000).
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Impact of human disturbances In some study locations, harbor seals disturbed by people 2/3 or more of the day. In some study locations, harbor seals disturbed by people 2/3 or more of the day. Human activity causes seals to rapidly flee from haul-out sites or “flush” into the water. After a flushing event, haul-out numbers infrequently or never recover fully. Human activity causes seals to rapidly flee from haul-out sites or “flush” into the water. After a flushing event, haul-out numbers infrequently or never recover fully. With persistent human encroachment, seals known to permanently abandon a haul-out site (Strawberry Pit) With persistent human encroachment, seals known to permanently abandon a haul-out site (Strawberry Pit)
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People have flushed all seals off the beach
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Effects of visitors on the behavior of harbor seals at Glacier Bay. Lewis 2000 Results showed pedestrians disturbed the highest percent of seals at 95% and caused the greatest average rate of disturbance - 84 seals per hour. Results showed pedestrians disturbed the highest percent of seals at 95% and caused the greatest average rate of disturbance - 84 seals per hour. Average minimal approach distance from hauled out seals for pedestrians averaged 147 yards. Average minimal approach distance from hauled out seals for pedestrians averaged 147 yards.
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Study conducted at Children’s Pool Beach in La Jolla. Yochem 2005 Disturbances associated with heavy demolition and construction activities only caused seals to flush into the water once. Disturbances associated with heavy demolition and construction activities only caused seals to flush into the water once. In contrast, humans on land or in the water resulted in 144 flush events. In contrast, humans on land or in the water resulted in 144 flush events. Results reflect massive impact by humans on the La Jolla harbor seals. Results reflect massive impact by humans on the La Jolla harbor seals.
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Behavioral responses of harbor seals to human-induced disturbances Anderson 2011 Determined boundaries on land should be >1,394 feet from the haul-out area to achieve adequate year-round protection Determined boundaries on land should be >1,394 feet from the haul-out area to achieve adequate year-round protection Observed seals more likely to flee from disturbances when they are without pups, since pups can’t flee as easily as adults Observed seals more likely to flee from disturbances when they are without pups, since pups can’t flee as easily as adults Reinforces the need for protection during nonpupping season. Reinforces the need for protection during nonpupping season.
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Clearly, the 20 foot distance limit from hauled out seals currently in effect at Children’s Pool Beach is far less than the distances recommended in these studies or by NOAA.
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Summary Many scientific studies have shown that when humans get too close to marine mammals, they harass and disturb their normal behavior. Many scientific studies have shown that when humans get too close to marine mammals, they harass and disturb their normal behavior. When people unintentionally or intentionally disturb these animals, it is a direct violation of the MMPA. When people unintentionally or intentionally disturb these animals, it is a direct violation of the MMPA.
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Summary Without a rope, visitors routinely approach seals resting on the beach too closely, causing them to rush frantically into the water. Without a rope, visitors routinely approach seals resting on the beach too closely, causing them to rush frantically into the water. Year round use of this thin guideline rope offers protection for the seals by sending a clear message to visitors to stay behind the rope when viewing the seals. Year round use of this thin guideline rope offers protection for the seals by sending a clear message to visitors to stay behind the rope when viewing the seals.
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Please grant the City’s request for a year- round guideline rope at Children’s Pool Beach to help alleviate the cruel harassment currently being inflicted on this seal rookery.
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References Andersen SM, Teilmann J et al. 2011. Behavioural responses of harbour seals to human-induced disturbances, Aquatic Conservation: Mar. Freshw. Ecosyst. 22:113-121. Brasseur, S., J. Creuwels, B. Werf and P. Reijnders. 1996. Deprivation indicates necessity for haul-out in harbor seals. Marine Mammal Science 12(4):619-624. Lewis TM, Mathews EA. 2000. Effects of human visitors on the behavior of harbor seals (Phoca vitulina richardsi) at McBride Gracier Fjord, Glacier Bay National Park. Report to Glacier Bay national Park, Resource Management Division. Yochem P. 2005. Summary of conclusions regarding the harbor seal rookery at Children’s Pool Beach, La Jolla, CA. La Jolla Cove Wall Replacement and Bluff Improvements Project (Sept 21, 2004 – Jan 1, 2005). March 25, 2005. Hubbs- SeaWorld Research Institute Paper.
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