Eastern Australia (E1 breeding grounds) may be a wintering destination for Area V Humpback Whales (Megaptera novaeangliae) migrating through New Zealand waters
Franklin, W, Franklin, T, Brooks, L, Gibbs, N, Childerhouse, S, Burns, D, Paton, D, Garrigue, C, Constantine, R, Poole, M, Hauser, N, Donoghue, M, Russell, K, Mattila, DK, Robbins, J, Anderson, M, Olavarria, C, Jackson, J, Noad, M, Harrison, P, Baverstock, P, Leaper, R, Baker, S & Clapman, P 2008, 'Eastern Australia (E1 breeding grounds) may be a wintering destination for Area V Humpback Whales (Megaptera novaeangliae) migrating through New Zealand waters', paper presented to IWC Scientific Committee SC/60/SH3.
Investigation of the migratory movement of humpback whales past New Zealand in the 1950s and early 1960ssuggested that the primary factor influencing the migratory flow past New Zealand was behaviour associatedwith breeding and feeding. To the north humpback whales gathered in concentrated breeding assemblages, alongthe Great Barrier Reef, Australia and nearby islands of the Western Pacific, at locations with suitable coastalconditions. 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 andOceania and Antarctic Area V feeding areas and also revealed low levels of intermingling of individualhumpbacks between isolated tropical breeding grounds in Western Australia, Eastern Australia and Oceania. Asimultaneous, near total collapse of the Eastern Australian, Norfolk Island, New Zealand and Oceania stocksoccurred in the early 1960’s as a result of commercial whaling, particularly the illegal whaling conducted by theSoviets in the Area V feeding areas. Recent photo-identification and genetic studies have identified at least 5discrete breeding sub-populations in Australia and Oceania; Western Australia (D), Eastern Australia (E1), NewCaledonia (E2), Tonga (E3) and Cook Island’s and French Polynesia (F). Also evident are low levels ofintermingling 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 onegenotype 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 areasand 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 weuse recent photo-identification data to investigate and discuss the migratory destination of humpback whalestraveling through New Zealand waters and suggest the hypothesis that humpbacks with site fidelity to EasternAustralia may migrate past the South Island of New Zealand including through the Cook Strait and FoveauxStrait.