Monitoring Kittlitz’s and marbled murrelets in Glacier Bay National Park and Preserve: 2018 annual report
Sergeant CJ and Johnson WF. 2018. Monitoring Kittlitz’s and marbled murrelets in Glacier Bay National Park and Preserve: 2018 annual report. Natural Resource Report. NPS/SEAN/NRR—2018/1711. National Park Service. Fort Collins, Colorado
Since 2009, the National Park Service’s Southeast Alaska Inventory and Monitoring Network (SEAN) has monitored population abundance and spatial distribution of Kittlitz's (KIMU) and marbled murrelets (MAMU) in Glacier Bay National Park and Preserve, an important summer residence for both species. The monitoring program design focuses on KIMU, with secondary consideration of MAMU. The SEAN uses boat-based line transect surveys to estimate species-specific, on-water density and abundance of murrelets, accounting for detection probability and unidentified murrelets. We surveyed 46 transects totaling 243 km from 4-9 July 2018 across the 1,170 km2 survey area in Glacier Bay proper. We estimated an abundance of 10,517 KIMU (SE = 2,655) and 52,302 MAMU (SE = 7,752). Estimated KIMU abundance increased 19% from 2017. MAMU abundance was slightly below the ten-year monitoring average and decreased 12% from 2017. From 2009 to 2018, KIMU abundance estimates have ranged from 7,025 to 16,469 (10-year mean = 10,224), while MAMU have ranged from 28,978 to 84,428 (10-year mean = 63,310). Please refer to the synthesis and program review report for monitoring of Kittlitz's murrelets in Glacier Bay National Park and Preserve which contains important findings that may affect the interpretation of abundance estimates (Hoekman, S. T. 2019. Kittlitz’s murrelet monitoring in Glacier Bay National Park and Preserve 2010–2018: Synthesis and program review. Natural Resource Report NPS/SEAN/NRR—2019/1957. National Park Service, Fort Collins, Colorado, https://irma.nps.gov/DataStore/Reference/Profile/2265288). The report summarizes the results of murrelet monitoring from 2010-2018, assesses monitoring performance and capacity to meet protocol objectives, and provides recommendations for potential enhancements to the monitoring protocol. Hoekman (2019) identifies misidentification and partial identification of murrelets which can bias abundance estimation and spatially-explicit density estimates, particularly for rare species, such as Kittlitz’s murrelets.
- Type
- Published Report
- Authors
- Sergeant, Christopher; Johnson, William
- Date of Issue
- 2018-09
- Publisher
- National Park Service
- Units
- GLBA , NRSS , SEAN
- Keywords
- Brachyramphus, distance surveys, Kittlitz's Murrelet, Line transects, Marbled Murrelet, marine ecosystem, pelagic
- Subjects
- Ecological Framework: Biological Integrity | Focal Species or Communities | Marine Communities , Ecological Framework: Biological Integrity | Focal Species or Communities | Birds