Eastern Australia (E1 breeding grounds) may be a wintering destination for Area V Humpback Whales (Megaptera novaeangliae) migrating through New Zealand waters

Investigation of the migratory movement of humpback whales past New Zealand in the 1950s and early 1960s suggested that the primary factor influencing the migratory flow past New Zealand was behaviour associated with breeding and feeding. To the north humpback whales gathered in concentrated breeding assemblages, along the Great Barrier Reef, Australia and nearby islands of the Western Pacific, at locations with suitable coastal conditions. To the south humpback whales dispersed widely across the Antarctic Area V feeding areas. Discovery Tag marks provided the first evidence of linkages between Eastern Australia, New Zealand and Oceania and Antarctic Area V feeding areas and also revealed low levels of intermingling of individual humpbacks between isolated tropical breeding grounds in Western Australia, Eastern Australia and Oceania. A simultaneous, near total collapse of the Eastern Australian, Norfolk Island, New Zealand and Oceania stocks occurred in the early 1960's as a result of commercial whaling, particularly the illegal whaling conducted by the Soviets in the Area V feeding areas. Recent photo-identification and genetic studies have identified at least 5 discrete breeding sub-populations in Australia and Oceania; Western Australia (D), Eastern Australia (E1), New Caledonia (E2), Tonga (E3) and Cook Island's and French Polynesia (F). Also evident are low levels of intermingling amongst breeding sub-populations consistent with the degree of genetic differentiation. Photo- identification has confirmed linkages between Antarctic Area V feeding areas and Eastern Australia and one genotype match has been reported between Antarctic Area V feeding areas and Oceania breeding grounds. Recent abundance estimates show steady increases of the Eastern Australian population, some recovery in the New Caledonia and Tonga population with little evidence of recovery at other known Oceania breeding areas and in New Zealand. Studies to date have provided no conclusive evidence of the migratory destination of the New Zealand population traveling from Antarctic Area V feeding areas to tropical breeding grounds. Here we use recent photo-identification data to investigate and discuss the migratory destination of humpback whales traveling through New Zealand waters and suggest the hypothesis that humpbacks with site fidelity to Eastern Australia may migrate past the South Island of New Zealand including through the Cook Strait and Foveaux Strait.