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• 1. [Article] Humpback whales (Megaptera novaeangliae) in the South Pacific breeding grounds : an allocation from feeding areas and an abundance estimate of whales specific to French Polynesia waters

  South Pacific humpback whales were devastated by commercial whaling in their Antarctic feeding areas during the 20th century. Understanding migratory connections and current abundance of these isolated ...

  Citation × Citation Citation Abstract Copy Title: Humpback whales (Megaptera novaeangliae) in the South Pacific breeding grounds : an allocation from feeding areas and an abundance estimate of whales specific to French Polynesia waters Author: Gibb, Giselle Renee South Pacific humpback whales were devastated by commercial whaling in their Antarctic feeding areas during the 20th century. Understanding migratory connections and current abundance of these isolated breeding stocks is crucial for the allocation of historical Antarctic catches in population dynamic models used to assess current recovery. However, only a small number of migratory connections have been documented between Oceania breeding stocks within the South Pacific and feeding areas in the Antarctic. In addition, little is known about abundance of these stocks which encompass a vast oceanic region. For this thesis I first used mixed-stock analysis (MSA) to allocate migratory connections from four Antarctic feeding areas (n=142) to seven South Pacific breeding stocks (n=1,373), including four in Oceania, based on genetic marker frequencies. The use of this method was justified by the breeding stocks showing genetic differentiation at the haplotype level with an F[subscript ST] value of 0.027 (p-value <0.001). The results showed a relatively strong connection of Western Australia to Antarctic Area IV, Tonga to the border of Antarctic Area VI/I, Colombia to the Antarctic Peninsula, and a split allocation of Eastern Australia and New Caledonia to Antarctic Area V. This study provides the first population-level information supporting previous individual-based studies that humpback whale migration may not necessarily be direct north south. Next, utilizing capture-recapture methodology of unique humpback whale fluke photographs, I estimated abundance of one of the least studied Oceania breeding stocks, French Polynesia, a stock which also showed no significant migratory allocation using MSA. Taking into consideration the possible advantages of using Quality Control (QC) photographs to minimize bias in matching, estimates were generated using the complete photo catalogue and also using only photographs adhering to QC criteria. I found that the choice of using QC has an effect on the abundance generated and discuss the implications of this finding. Despite the photo catalogue used, the French Polynesia stock is estimated to number less than 1,900 individuals. Lastly, to provide additional information on the French Polynesia stock I used photo-identification to compare French Polynesia whales to whales in the Antarctic Peninsula and Strait of Magellan (Antarctic Area I), a possible migratory connection suggested by previous microsatellite genotyping. No conclusive matches were found. Although this does not discount the possibility of a few migrants traveling between these regions it does indicate the Antarctic Peninsula and the Strait of Magellan are not primary feeding areas of French Polynesia. This new information regarding abundance and migration of French Polynesia whales is important for the Comprehensive Assessment of Southern Hemisphere humpback whales. This document is currently being completed as the International Whaling Commission considers the next critical steps in recovery for Oceania humpback whales stocks. Title: Humpback whales (Megaptera novaeangliae) in the South Pacific breeding grounds : an allocation from feeding areas and an abundance estimate of whales specific to French Polynesia waters Author: Gibb, Giselle Renee South Pacific humpback whales were devastated by commercial whaling in their Antarctic feeding areas during the 20th century. Understanding migratory connections and current abundance of these isolated breeding stocks is crucial for the allocation of historical Antarctic catches in population dynamic models used to assess current recovery. However, only a small number of migratory connections have been documented between Oceania breeding stocks within the South Pacific and feeding areas in the Antarctic. In addition, little is known about abundance of these stocks which encompass a vast oceanic region. For this thesis I first used mixed-stock analysis (MSA) to allocate migratory connections from four Antarctic feeding areas (n=142) to seven South Pacific breeding stocks (n=1,373), including four in Oceania, based on genetic marker frequencies. The use of this method was justified by the breeding stocks showing genetic differentiation at the haplotype level with an F[subscript ST] value of 0.027 (p-value <0.001). The results showed a relatively strong connection of Western Australia to Antarctic Area IV, Tonga to the border of Antarctic Area VI/I, Colombia to the Antarctic Peninsula, and a split allocation of Eastern Australia and New Caledonia to Antarctic Area V. This study provides the first population-level information supporting previous individual-based studies that humpback whale migration may not necessarily be direct north south. Next, utilizing capture-recapture methodology of unique humpback whale fluke photographs, I estimated abundance of one of the least studied Oceania breeding stocks, French Polynesia, a stock which also showed no significant migratory allocation using MSA. Taking into consideration the possible advantages of using Quality Control (QC) photographs to minimize bias in matching, estimates were generated using the complete photo catalogue and also using only photographs adhering to QC criteria. I found that the choice of using QC has an effect on the abundance generated and discuss the implications of this finding. Despite the photo catalogue used, the French Polynesia stock is estimated to number less than 1,900 individuals. Lastly, to provide additional information on the French Polynesia stock I used photo-identification to compare French Polynesia whales to whales in the Antarctic Peninsula and Strait of Magellan (Antarctic Area I), a possible migratory connection suggested by previous microsatellite genotyping. No conclusive matches were found. Although this does not discount the possibility of a few migrants traveling between these regions it does indicate the Antarctic Peninsula and the Strait of Magellan are not primary feeding areas of French Polynesia. This new information regarding abundance and migration of French Polynesia whales is important for the Comprehensive Assessment of Southern Hemisphere humpback whales. This document is currently being completed as the International Whaling Commission considers the next critical steps in recovery for Oceania humpback whales stocks. Close

• 2. [Article] Spatio-Temporal Analysis and Modeling in the Marine Environment : Humpback Whale Genetic Variability and Seabird Distributions in the Northeastern Pacific Ocean

  The rapid decline of marine ecosystems worldwide and the failure of traditional single species management pushed for the development of ecosystem-based conservation measures such as marine protected areas ...

  Citation × Citation Citation Abstract Copy Title: Spatio-Temporal Analysis and Modeling in the Marine Environment : Humpback Whale Genetic Variability and Seabird Distributions in the Northeastern Pacific Ocean Author: Dick, Dorothy Marie The rapid decline of marine ecosystems worldwide and the failure of traditional single species management pushed for the development of ecosystem-based conservation measures such as marine protected areas (MPA) to slow the loss of marine biodiversity. One approach to MPA creation advocates targeting marine megafauna (e.g., marine mammals, seabirds, sharks, etc.) and assumes protective measures for megafauna will extend safeguards to areas of ocean productivity and other species dependent on that productivity. The marine spatial planning (MSP) process requires spatially-explicit information resulting in the development of map products used in planning and decision making. The crux of map creation is georeferenced species occurrence data. This three-part study takes a multidisciplinary approach, combining geography, marine conservation, molecular ecology, and spatial ecology to explore species occurrence data and development of novel geoanalytical tools, spatial analyses, and predictive modeling to inform the MSP process and help design more effective MPA networks for North Pacific marine megafauna (humpback whales and seabirds). Chapter 2 includes the development of geneGIS, a customized Arc Marine data model and suite of computational GIS tools to explore, analyze, and visualize spatially-explicit, individual-based records from North Pacific humpback whale photo-identification and genetic data. Unlike most occurrence data, this presence-only dataset is enriched by the addition of genetic information enabling mangers to factor in population structure and genetic diversity, and thus maximize species resilience, when designing MPAs. Chapters 3 and 4 focus on using presence-absence data to develop spatially-explicit ecological models to identify multispecies seabird foraging aggregations (hotspots) and assess how these locations may shift with climate change within the California Current System. Key to both components is an improved understanding of what factors influence the presence of a species and/or its genetic variability to enable present day planning and design of MPA networks to ensure adequate protection will be in place now and as climate change progresses. This information can also be used to inform policy decisions by adapting strategies to reduce non-climate stressors such as fishery pressures and coastal development in areas predicted to be important to marine species in the future. Title: Spatio-Temporal Analysis and Modeling in the Marine Environment : Humpback Whale Genetic Variability and Seabird Distributions in the Northeastern Pacific Ocean Author: Dick, Dorothy Marie The rapid decline of marine ecosystems worldwide and the failure of traditional single species management pushed for the development of ecosystem-based conservation measures such as marine protected areas (MPA) to slow the loss of marine biodiversity. One approach to MPA creation advocates targeting marine megafauna (e.g., marine mammals, seabirds, sharks, etc.) and assumes protective measures for megafauna will extend safeguards to areas of ocean productivity and other species dependent on that productivity. The marine spatial planning (MSP) process requires spatially-explicit information resulting in the development of map products used in planning and decision making. The crux of map creation is georeferenced species occurrence data. This three-part study takes a multidisciplinary approach, combining geography, marine conservation, molecular ecology, and spatial ecology to explore species occurrence data and development of novel geoanalytical tools, spatial analyses, and predictive modeling to inform the MSP process and help design more effective MPA networks for North Pacific marine megafauna (humpback whales and seabirds). Chapter 2 includes the development of geneGIS, a customized Arc Marine data model and suite of computational GIS tools to explore, analyze, and visualize spatially-explicit, individual-based records from North Pacific humpback whale photo-identification and genetic data. Unlike most occurrence data, this presence-only dataset is enriched by the addition of genetic information enabling mangers to factor in population structure and genetic diversity, and thus maximize species resilience, when designing MPAs. Chapters 3 and 4 focus on using presence-absence data to develop spatially-explicit ecological models to identify multispecies seabird foraging aggregations (hotspots) and assess how these locations may shift with climate change within the California Current System. Key to both components is an improved understanding of what factors influence the presence of a species and/or its genetic variability to enable present day planning and design of MPA networks to ensure adequate protection will be in place now and as climate change progresses. This information can also be used to inform policy decisions by adapting strategies to reduce non-climate stressors such as fishery pressures and coastal development in areas predicted to be important to marine species in the future. Close