To investigate the incidence of non-lethal predation in Southern Hemisphere whales, more than 3400 fluke-identification photographs from resight histories of 1436 east Australian humpback whales were examined for evidence of predatory markings. Photographs were obtained from 1984 to 1996 at various locations along the east coast of Australia, from northern Queensland to southern New South Wales. Photographs were classified in terms of the level and type of scarring. The possible predator and whether the markings appeared fresh were also noted. In all, 17% of identified east Australian humpbacks possessed some form of predatory scarring, 57% of which was minor and 43% major. Almost all predatory scarring was consistent with that inflicted by killer whales. Only three whales demonstrated an increase in the level of predatory scarring after their first sightings. Two incidents of fresh scarring were recorded, and one fatal killer whale attack on a humpback whale calf was directly observed. The overall level of predatory scarring found in this study is comparable to those found in studies for Northern Hemisphere humpback whales. The low incidence of adult whales showing their first sign of predatory scarring after their initial sighting, and the small number possessing recent scarring, support the idea that east Australian humpback whales experience most predatory attacks early in life.

Animal movement plays a fundamental role in the ecology of migratory species, and understanding migration patterns is required for effective management. To evaluate intrinsic and environmental factors associated with probabilities of endangered North Atlantic right whales Eubalaena glacialis migrating to a wintering ground off the southeastern United States (SEUS), we applied a multistate temporary emigration capture-recapture model to 22 years of photo-identification data. Migration probabilities for juveniles were generally higher yet more variable than those for adults, and non-calving adult females were the least likely group to migrate. The highest migration probabilities for juveniles and adult males coincided with years of relatively high calving rates, following years of higher prey availability in a fall feeding ground. Right whale migration to the SEUS can be classified as condition-dependent partial migration, which includes skipped breeding partial migration for reproductive females, and is likely influenced by tradeoffs among ecological factors such as reproductive costs and foraging opportunities that vary across individuals and time. The high variability in migration reported in this study provides insight into the ecological drivers of migration but presents challenges to right whale monitoring and conservation strategies.

Effective conservation of endangered North Atlantic right whales Eubalaena glacialis requires information about their spatio-temporal distribution. Understanding temporal distribution is particularly important, because a portion of the population migrates between high-latitude summer feeding grounds off the northeastern US and Canadian Maritimes coasts and lower-latitude calving and wintering grounds off the southeastern US coast (SEUS). Here, we modeled SEUS residence patterns using photo-identification data from coastal South Carolina, Georgia, and Florida from 7 winter seasons (2004/2005-2010/2011). We used multistate open robust design models to evaluate effects of reproductive status, demographic group, and environmental conditions on SEUS residence. Model estimates accounted for temporal variation and imperfect detection and provided probabilities of entering the SEUS, staying in the SEUS, and being sighted in the SEUS. We also derived estimates for residence time and seasonal abundance. We observed staggered arrival and departure patterns and demographic differences in residence patterns that are characteristic of a differential migration strategy. Calving females arrived ear liest and, in most seasons, had mean residence periods more than twice as long as other demographic groups. Conversely, adult males arrived the latest and had the shortest residence times. Within-season detection was positively influenced by survey effort, and overall seasonal mean (± SE) detection rate estimates ranged from 0.83 ± 0.08 for non-calving adult females to 0.98 ± 0.02 for calving females. Results provide insights into right whale behavior, biology, and temporal distribution in the SEUS and can be used to evaluate spatially and temporally dynamic management measures.

‘Discovery’ marks and their recoveries from humpback whales in the southwest Pacific provide no evidence of migratory interchange between wintering grounds in New Caledonia and migratory corridors off east Australia (Moreton Island) and New Zealand, or wintering grounds in Tonga. To provide further insight into the migratory connections among these regions, images of 169 individually-identified humpback whales from New Caledonia were compared with the published catalogues of Australian (n = 1,088), Tongan (n = 78) and New Zealand (n = 1) humpback whales. Four of the New Caledonian humpbacks were found to have migrated past east Australia and one past New Zealand in separate years. No movement was found between New Caledonia and Tonga. These data provide the first photographic information on exchanges between regions of the southwest Pacific. Reviewed in light of historical records, these data also highlight the necessity for further research in the South Pacific region to resolve the question of the proposed segregation of the Southern Hemisphere Group V stock into an eastern group (New Zealand and the Pacific Islands) and a western group (east Australia).