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Blue whales are infrequently reported from New Zealand and their taxonomic status is unclear. Here we present new information on the residency, external morphology, and habitat use of blue whales encountered in New Zealand waters. Thirty-one blue whales were photo-identified around the North and South Islands of New Zealand from 2004 to 2014 in seven different months of the year. One photographic match was found between June 2011 and March 2013: the first evidence that an individual blue whale has remained in or returned to New Zealand waters in different years and seasons. Observations of the external morphology of blue whales encountered off the South Island confirm that there is a shorter, non-Antarctic form of blue whale occurring near New Zealand. Body length and proportion, head shape, body condition, and skin condition were similar to Australian but not Antarctic blue whales. In 2013, feeding behavior was observed off the South Island's west coast and strong evidence of feeding was observed off the east coast and is the first reported occurrence of feeding for these locations. Feeding behavior was also observed in the Hauraki Gulf in November 2010. Feeding in these widely spread locations, in addition to the recently reported foraging ground in the South Taranaki Bight, suggest that New Zealand coastal waters are a feeding area for blue whales.
Humpback whale (Megaptera novaeangliae) populations typically undertake seasonal migrations, spending winters in low latitude breeding grounds and summers foraging in high latitude feeding grounds. Until recently, a broad scale understanding of whale movement has been derived from whaling records, Discovery marks, photo identification and genetic analyses. However, with advances in satellite tagging technology and concurrent development of analytical methodologies we can now detail finer scale humpback whale movement, infer behavioural context and examine how these animals interact with their physical environment. Here we describe the temporal and spatial characteristics of migration along the east Australian seaboard and into the Southern Ocean by 30 humpback whales satellite tagged over three consecutive austral summers. We characterise the putative Antarctic feeding grounds and identify supplemental foraging within temperate, migratory corridors. We demonstrate that Antarctic foraging habitat is associated with the marginal ice zone, with key predictors of inferred foraging behaviour including distance from the ice edge, ice melt rate and variability in ice concentration two months prior to arrival. We discuss the highly variable ice season within the putative foraging habitat and the implications that this and other environmental factors may have on the continued strong recovery of this humpback whale population.
9 INTRODUCTION 10 METHODS 13 Population definition in the Southern Hemisphere 13 Sample collection, DNA extraction and sex identification 13 Microsatellite loci 14 Microsatellite validation 15 mtDNA 15 Statistical analysis 16 RESULTS 19 Sample size and sex ratio 19 Genetic diversity 20 Genetic differentiation and population structure analysis 21 DISCUSSION 23
Abstract Here we report on an ultra‐sensitive colorimetric sensing platform that takes advantage of both the strong amplification power of rolling circle amplification (RCA) and the high efficiency of a simple urease‐mediated litmus test. The presence of a target triggers the RCA reaction, and urease‐labelled DNA can hybridize to the biotinylated RCA products and be immobilized onto streptavidin‐coated magnetic beads. The urease‐laden beads are then used to hydrolyze urea, leading to an increase in pH that can be detected by a simple litmus test. We show this sensing platform can be easily integrated with aptamers for sensing diverse targets via the detection of human thrombin and platelet‐derived growth factor (PDGF) utilizing structure‐switching aptamers as well as SARS‐CoV‐2 in human saliva using a spike‐binding trimeric DNA aptamer. Furthermore, we demonstrate that this colorimetric sensing platform can be integrated into a simple paper‐based device for sensing applications.
Abstract Humpback whales undertake long‐distance seasonal migrations between low latitude winter breeding grounds and high latitude summer feeding grounds. We report the first in‐depth population genetic study of the humpback whales that migrate to separate winter breeding grounds along the northwestern and northeastern coasts of Australia, but overlap on summer feeding grounds around Antarctica. Weak but significant differentiation between eastern and western Australia was detected across ten microsatellite loci ( F ST = 0.005, P = 0.001; D EST = 0.031, P = 0.001, n = 364) and mitochondrial control region sequences ( F ST = 0.017 and Φ ST = 0.069, P = 0.001, n = 364). Bayesian clustering analyses using microsatellite data could not resolve any population structure unless sampling location was provided as a prior. This study supports the emerging evidence that weak genetic differentiation is characteristic among neighboring Southern Hemisphere humpback whale breeding populations. This may be a consequence of relatively high gene flow facilitated by overlapping summer feeding areas in Antarctic waters.
While preparing a review of published descriptions of copulatory behaviour in macropod marsupials (McLean, Lundie-Smith and Jarman 1993), we were surprised to find no description for one of the most studied species, the quokka (Setonix brachyurus, e.g. see Bradshaw 1983). Copulating quokkas have been seen previously by researchers (e.g. Kitchener 1970), but no account was given. Here we provide descriptions of copulatory behaviour in quokkas, and comment on levels of sexual behaviour and activity by quokkas in the wild and in captivity.