The following report summarizing humpback whale monitoring results from 2022 is now available:
Neilson, J.L., C.M. Gabriele, and L.E. McCaslin. 2023. Glacier Bay & Icy Strait Humpback Whale Population Monitoring: 2022 Update. National Park Service Resource Brief, Gustavus, Alaska. Glacier Bay & Icy Strait Humpback Whale Population Monitoring: 2022 Update (nps.gov)<https://irma.nps.gov/DataStore/DownloadFile/682953> [1.7 MB, 8 pages] The 2023 field season (our 39th year of monitoring) will be underway soon! KEY FINDINGS FROM 2022: * The total number of whales in Glacier Bay-Icy Strait (GB-IS) was similar to 2021. In Glacier Bay, abundance increased compared to 2021, while in Icy Strait, abundance decreased. * Thirty-one of 66 adult whales (47%) with a history of strong site fidelity to GB-IS were missing and most are presumed to have died during or after the 2014-2016 Northeast Pacific marine heatwave (PMH). * We documented six mother/calf pairs and a declining crude birth rate (CBR) since 2020 (2020: 7.4%; 2021: 6.5%, 2022: 3.6%). Although calf production appeared to be rebounding in 2020 following sharp declines during and after the PMH, it remains far below the pre-PMH mean CBR of 9.1%. * Juvenile survival appears to be increasing after an abrupt decline during and after the PMH. * Relatively high residency and low transience rates in 2019-2022 presumably reflect favorable feeding conditions in GB-IS in contrast to PMH years. * The rate of emaciation (16%) appeared to be lower in 2022 than in recent years and reverses a pattern of increasing emaciation. * In February 2022, adult female #235/”Spot” (age ≥49) was found dead near Angoon and a necropsy revealed that she likely died after being hit by a large vessel. * We opportunistically documented forage fish, especially sand lance, but annual forage fish monitoring is needed to systematically assess whale prey trends. -- Janet Neilson Humpback Whale Monitoring Program Glacier Bay National Park & Preserve PO Box 140 Gustavus, AK 99826 907-697-2658 Xunaa Káawu Aaní áwé yéi xat yatee ka ax’ yéi jixané I live and work in Huna Tlingit Homeland.
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