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• 1. [Article] Factors Affecting Snowy Plover Chick Survival in a Managed Population

  Understanding survival of precocial chicks in the period immediately following hatching has important conservation implications because population growth is often sensitive to post-hatching survival. We ...

  Citation × Citation Citation Abstract Copy Title: Factors Affecting Snowy Plover Chick Survival in a Managed Population Author: Dinsmore, Stephen J., Gaines, Eleanor P., Pearson, Scott F., Lauten, David J., Castelein, Kathleen J. Year: 2017 Understanding survival of precocial chicks in the period immediately following hatching has important conservation implications because population growth is often sensitive to post-hatching survival. We studied federally threatened Western Snowy Plover (Charadrius nivosus nivosus) broods at the northern limit of their range in coastal Oregon (n ¼ 1,157) and Washington (n ¼ 84) from 1991 to 2011 in an attempt to understand seasonal, annual, and spatial patterns of chick survival. In Oregon, plover chick survival increased with age, varied between sites, and was greater at sites with predator management. The mean probability of surviving from hatch to fledging at 28 days of age in Oregon was 0.57 (95% CI: 0.50, 0.63). In Washington, where predator management was not employed, we conducted separate analyses using individually banded and unbanded chicks and results indicated that survival generally increased with chick age. The mean estimated probability of surviving from hatch to fledging at 28 days of age in Washington was 0.27 (95% CI: 0.20, 0.35) for individually banded chicks when perfect detection was assumed. This probability increased to 0.67 (95% CI: 0.41, 0.83) when we analyzed unbanded chicks and included detection probability. Our findings confirm the importance of considering age effects in the survival of Snowy Plover chicks and raise questions about the validity of assuming perfect detection of plover chicks during brood checks. This work also highlights the benefit of predator management on chick survival. Title: Factors Affecting Snowy Plover Chick Survival in a Managed Population Author: Dinsmore, Stephen J., Gaines, Eleanor P., Pearson, Scott F., Lauten, David J., Castelein, Kathleen J. Year: 2017 Understanding survival of precocial chicks in the period immediately following hatching has important conservation implications because population growth is often sensitive to post-hatching survival. We studied federally threatened Western Snowy Plover (Charadrius nivosus nivosus) broods at the northern limit of their range in coastal Oregon (n ¼ 1,157) and Washington (n ¼ 84) from 1991 to 2011 in an attempt to understand seasonal, annual, and spatial patterns of chick survival. In Oregon, plover chick survival increased with age, varied between sites, and was greater at sites with predator management. The mean probability of surviving from hatch to fledging at 28 days of age in Oregon was 0.57 (95% CI: 0.50, 0.63). In Washington, where predator management was not employed, we conducted separate analyses using individually banded and unbanded chicks and results indicated that survival generally increased with chick age. The mean estimated probability of surviving from hatch to fledging at 28 days of age in Washington was 0.27 (95% CI: 0.20, 0.35) for individually banded chicks when perfect detection was assumed. This probability increased to 0.67 (95% CI: 0.41, 0.83) when we analyzed unbanded chicks and included detection probability. Our findings confirm the importance of considering age effects in the survival of Snowy Plover chicks and raise questions about the validity of assuming perfect detection of plover chicks during brood checks. This work also highlights the benefit of predator management on chick survival. Close

• 2. [Article] Predator Exclosures, Predator Removal, and Habitat Improvement Increase Nest Success of Snowy Plovers in Oregon, USA

  Management to increase reproductive success is commonly used to aid recovery of threatened and endangered species. The Western Snowy Plover (Charadrius nivosus nivosus) breeds from coastal Washington, ...

  Citation × Citation Citation Abstract Copy Title: Predator Exclosures, Predator Removal, and Habitat Improvement Increase Nest Success of Snowy Plovers in Oregon, USA Author: Dinsmore, Stephen J., Lauten, David J., Castelein, Kathleen J., Gaines, Eleanor P., Stern, Mark A. Year: 2014 Management to increase reproductive success is commonly used to aid recovery of threatened and endangered species. The Western Snowy Plover (Charadrius nivosus nivosus) breeds from coastal Washington, USA, to Baja California, Mexico, and in disjunct interior sites. The Pacific coast population is federally listed as Threatened; habitat loss and nest loss to a suite of terrestrial and avian predators are thought to be primary factors limiting population growth in this species. In coastal Oregon, USA, a consortium of state and federal management agencies deployed nest exclosures on active Snowy Plover nests, initiated a lethal predator management program, and conducted local-scale habitat management in an effort to boost local productivity. During 1990–2009, we monitored 1,951 Snowy Plover nests at 9 sites with varying treatments. We examined the effectiveness of 3 types of nest exclosures (large, small, and outfitted with electric wire), predator removal, and habitat management on nest survival. Habitat management to remove invasive grasses and provide more suitable nesting substrate more than doubled nest survival. Predator management or use of any of the 3 types of exclosures also affected nest survival. There appeared to be no additional benefit to using both approaches, but the biological relevance of these findings is unclear because of site differences in treatments applied. Importantly, these management techniques only affected nesting success; their effect on other contributions to population viability (e.g., fledging success) was not correlated with nesting success. This long-term study illustrates the short-term benefits and tradeoffs of using nest exclosures, predator management, and habitat restoration to improve nesting success. Although we gained broader insight into the relative efficacy of common management techniques to improve avian nesting success, we cannot yet determine how improved nest success contributes to population growth. Title: Predator Exclosures, Predator Removal, and Habitat Improvement Increase Nest Success of Snowy Plovers in Oregon, USA Author: Dinsmore, Stephen J., Lauten, David J., Castelein, Kathleen J., Gaines, Eleanor P., Stern, Mark A. Year: 2014 Management to increase reproductive success is commonly used to aid recovery of threatened and endangered species. The Western Snowy Plover (Charadrius nivosus nivosus) breeds from coastal Washington, USA, to Baja California, Mexico, and in disjunct interior sites. The Pacific coast population is federally listed as Threatened; habitat loss and nest loss to a suite of terrestrial and avian predators are thought to be primary factors limiting population growth in this species. In coastal Oregon, USA, a consortium of state and federal management agencies deployed nest exclosures on active Snowy Plover nests, initiated a lethal predator management program, and conducted local-scale habitat management in an effort to boost local productivity. During 1990–2009, we monitored 1,951 Snowy Plover nests at 9 sites with varying treatments. We examined the effectiveness of 3 types of nest exclosures (large, small, and outfitted with electric wire), predator removal, and habitat management on nest survival. Habitat management to remove invasive grasses and provide more suitable nesting substrate more than doubled nest survival. Predator management or use of any of the 3 types of exclosures also affected nest survival. There appeared to be no additional benefit to using both approaches, but the biological relevance of these findings is unclear because of site differences in treatments applied. Importantly, these management techniques only affected nesting success; their effect on other contributions to population viability (e.g., fledging success) was not correlated with nesting success. This long-term study illustrates the short-term benefits and tradeoffs of using nest exclosures, predator management, and habitat restoration to improve nesting success. Although we gained broader insight into the relative efficacy of common management techniques to improve avian nesting success, we cannot yet determine how improved nest success contributes to population growth. Close

• 3. [Article] The Distribution and Reproductive Success of the Western Snowy Plover along the Oregon Coast - 2016

  We monitored the distribution, abundance and productivity of the federally threatened Western Snowy Plover (Charadrius nivosus nivosus) along the Oregon coast from 5 April – 31 August 2016. From north ...

  Citation × Citation Citation Abstract Copy Title: The Distribution and Reproductive Success of the Western Snowy Plover along the Oregon Coast - 2016 Author: Lauten, David J., Castelein, Kathleen A., Farrar, J. Daniel, Kotaich, Adam A., Krygsman, Erica, Gaines, Eleanor P. Year: 2016 We monitored the distribution, abundance and productivity of the federally threatened Western Snowy Plover (Charadrius nivosus nivosus) along the Oregon coast from 5 April – 31 August 2016. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North and South Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Snowy Plover Management Area, New River HRA and adjacent lands, and Floras Lake. Our objectives in 2016 were to: 1) estimate the size of the adult Snowy Plover population, 2) locate plover nests, 3) determine nest success, 4) implement nest protection as appropriate (e.g. ropes, signs, exclosures), 5) develop and test a sampling technique to determine plover productivity, 6) monitor brood outcomes, and 7) collect general observational data about predators and use cameras to document predator activity at nests. We estimated the resident number of Snowy Plovers in Oregon at 518 individuals. The adult plover population was the highest estimate recorded since monitoring began in 1990. We monitored 694 nests in 2016. Overall apparent nest success was 25%. Nest failures were attributed to unknown depredation, unknown cause, harrier depredation, corvid depredation, mammalian depredation, gull depredation, one-egg nest, wind/weather, abandonment, overwashing and infertility. We monitored a sample of 150 of 192 known broods, and documented a minimum of 197 fledglings. Overall brood success was 71%, fledging success was 43%, but only 0.60 +/- 0.09 fledglings per male were produced. Title: The Distribution and Reproductive Success of the Western Snowy Plover along the Oregon Coast - 2016 Author: Lauten, David J., Castelein, Kathleen A., Farrar, J. Daniel, Kotaich, Adam A., Krygsman, Erica, Gaines, Eleanor P. Year: 2016 We monitored the distribution, abundance and productivity of the federally threatened Western Snowy Plover (Charadrius nivosus nivosus) along the Oregon coast from 5 April – 31 August 2016. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North and South Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Snowy Plover Management Area, New River HRA and adjacent lands, and Floras Lake. Our objectives in 2016 were to: 1) estimate the size of the adult Snowy Plover population, 2) locate plover nests, 3) determine nest success, 4) implement nest protection as appropriate (e.g. ropes, signs, exclosures), 5) develop and test a sampling technique to determine plover productivity, 6) monitor brood outcomes, and 7) collect general observational data about predators and use cameras to document predator activity at nests. We estimated the resident number of Snowy Plovers in Oregon at 518 individuals. The adult plover population was the highest estimate recorded since monitoring began in 1990. We monitored 694 nests in 2016. Overall apparent nest success was 25%. Nest failures were attributed to unknown depredation, unknown cause, harrier depredation, corvid depredation, mammalian depredation, gull depredation, one-egg nest, wind/weather, abandonment, overwashing and infertility. We monitored a sample of 150 of 192 known broods, and documented a minimum of 197 fledglings. Overall brood success was 71%, fledging success was 43%, but only 0.60 +/- 0.09 fledglings per male were produced. Close

• 4. [Article] The Distribution and Reproductive Success of the Western Snowy Plover along the Oregon Coast - 2015

  We monitored the distribution, abundance and productivity of the federally threatened Western Snowy Plover (Charadrius nivosus nivosus) along the Oregon coast from 3 April – 11 September 2015. From north ...

  Citation × Citation Citation Abstract Copy Title: The Distribution and Reproductive Success of the Western Snowy Plover along the Oregon Coast - 2015 Author: Lauten, David J., Castelein, Kathleen A., Farrar, J. Daniel, Kotaich, Adam A., Gaines, Eleanor P. Year: 2015 We monitored the distribution, abundance and productivity of the federally threatened Western Snowy Plover (Charadrius nivosus nivosus) along the Oregon coast from 3 April – 11 September 2015. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North and South Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Snowy Plover Management Area, New River HRA and adjacent lands, and Floras Lake. Our objectives in 2015 were to: 1) estimate the size of the adult Snowy Plover population along the Oregon coast, 2) locate plover nests, 3) determine nest success, 4) implement nest protection as appropriate (e.g. ropes, signs, exclosures), 5) determine fledging success, 6) monitor brood movements, and 7) collect general observational data about predators. We estimate the Snowy Plover breeding population in Oregon at 449 individuals; a minimum of 376 individuals were known to have nested. The adult plover population was the highest estimate recorded since monitoring began in 1990. We monitored 501 nests in 2015. Overall apparent nest success was 48%. Nest failures were attributed to unknown cause, unknown depredation, mammalian depredation, corvid depredation, abandonment, wind/weather, one-egg nests, harrier depredation, infertility, overwashing, gull depredation and human caused. We monitored 271 broods, including 32 from unknown nests, and documented a minimum of 333 fledglings. Overall brood success was 75%, fledging success was 49%, and 1.51 fledglings per male were produced. Title: The Distribution and Reproductive Success of the Western Snowy Plover along the Oregon Coast - 2015 Author: Lauten, David J., Castelein, Kathleen A., Farrar, J. Daniel, Kotaich, Adam A., Gaines, Eleanor P. Year: 2015 We monitored the distribution, abundance and productivity of the federally threatened Western Snowy Plover (Charadrius nivosus nivosus) along the Oregon coast from 3 April – 11 September 2015. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North and South Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Snowy Plover Management Area, New River HRA and adjacent lands, and Floras Lake. Our objectives in 2015 were to: 1) estimate the size of the adult Snowy Plover population along the Oregon coast, 2) locate plover nests, 3) determine nest success, 4) implement nest protection as appropriate (e.g. ropes, signs, exclosures), 5) determine fledging success, 6) monitor brood movements, and 7) collect general observational data about predators. We estimate the Snowy Plover breeding population in Oregon at 449 individuals; a minimum of 376 individuals were known to have nested. The adult plover population was the highest estimate recorded since monitoring began in 1990. We monitored 501 nests in 2015. Overall apparent nest success was 48%. Nest failures were attributed to unknown cause, unknown depredation, mammalian depredation, corvid depredation, abandonment, wind/weather, one-egg nests, harrier depredation, infertility, overwashing, gull depredation and human caused. We monitored 271 broods, including 32 from unknown nests, and documented a minimum of 333 fledglings. Overall brood success was 75%, fledging success was 49%, and 1.51 fledglings per male were produced. Close

• 5. [Article] The Distribution and Reproductive Success of the Western Snowy Plover along the Oregon Coast - 2014

  We monitored the distribution, abundance and productivity of the federally threatened Western Snowy Plover (Charadrius nivosus nivosus) along the Oregon coast from 1 April – 15 September 2014. From north ...

  Citation × Citation Citation Abstract Copy Title: The Distribution and Reproductive Success of the Western Snowy Plover along the Oregon Coast - 2014 Author: Lauten, David J., Castelein, Kathleen J., Farrar, J. Daniel, Kotaich, Adam A., Gaines, Eleanor P. Year: 2014 We monitored the distribution, abundance and productivity of the federally threatened Western Snowy Plover (Charadrius nivosus nivosus) along the Oregon coast from 1 April – 15 September 2014. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North and South Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Snowy Plover Management Area, New River HRA and adjacent lands, and Floras Lake. Our objectives in 2014 were to: 1) estimate the size of the adult Snowy Plover population along the Oregon coast, 2) locate plover nests, 3) determine nest success, 4) use mini-exclosures (MEs) to protect nests from predators as needed, 5) determine fledging success, 6) monitor brood movements, and 7) collect general observational data about predators. We observed an estimated 338 adult Snowy Plovers; a minimum of 280 individuals were known to have nested. The adult plover population was the highest estimate recorded since monitoring began in 1990. We monitored 346 nests in 2014. Overall apparent nest success was 60%. Nest failures were attributed to unknown depredation, unknown cause, mammalian depredation, abandonment, wind/weather, one-egg nests, avian depredation, overwashed, infertility, and corvid depredation. We monitored 221 broods, including 12 from unknown nests, and documented a minimum of 272 fledglings. Overall brood success was 77%, fledging success was 48%, and 1.68 fledglings per male were produced. Title: The Distribution and Reproductive Success of the Western Snowy Plover along the Oregon Coast - 2014 Author: Lauten, David J., Castelein, Kathleen J., Farrar, J. Daniel, Kotaich, Adam A., Gaines, Eleanor P. Year: 2014 We monitored the distribution, abundance and productivity of the federally threatened Western Snowy Plover (Charadrius nivosus nivosus) along the Oregon coast from 1 April – 15 September 2014. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North and South Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Snowy Plover Management Area, New River HRA and adjacent lands, and Floras Lake. Our objectives in 2014 were to: 1) estimate the size of the adult Snowy Plover population along the Oregon coast, 2) locate plover nests, 3) determine nest success, 4) use mini-exclosures (MEs) to protect nests from predators as needed, 5) determine fledging success, 6) monitor brood movements, and 7) collect general observational data about predators. We observed an estimated 338 adult Snowy Plovers; a minimum of 280 individuals were known to have nested. The adult plover population was the highest estimate recorded since monitoring began in 1990. We monitored 346 nests in 2014. Overall apparent nest success was 60%. Nest failures were attributed to unknown depredation, unknown cause, mammalian depredation, abandonment, wind/weather, one-egg nests, avian depredation, overwashed, infertility, and corvid depredation. We monitored 221 broods, including 12 from unknown nests, and documented a minimum of 272 fledglings. Overall brood success was 77%, fledging success was 48%, and 1.68 fledglings per male were produced. Close