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The family Ziphiidae (beaked whales) are one of the least known of all vertebrate groups. Small to medium-sized cetaceans, 3.5 - 12 m in length, beaked whales are found in deep, pelagic waters of all ocean basins except the highest latitudes of the Arctic. With their incredible diving capacity (some species make regular dives of over an hour down to 1400 m or more), relatively low abundance, and elusive behaviour, these squid-eating whales are generally very difficult to study at sea. Most of what is known has come from the remains of dead stranded specimens. This large family consists of 21 species scattered over 6 genera. The vast majority of these species belong to the genus Mesoplodon (n = 14 and counting). All the other genera are monotypic or consist of antitropical north-south species pairs.

 

There is comparatively little differentiation in external morphology among Mesoplodon species, with the exception of the large tusk-like teeth of the adult males. (Females and juveniles are effectively toothless - the single pair of teeth do not develop and remain hidden in the gum). These tusks are not used for feeding. Instead, the males use them as weapons in intra-specific combat with other males. This has never been observed but has been inferred from the deep tooth-rake scars typically observed on the backs of adult male beaked whales.

 

We are using nuclear introns and mitochondrial DNA sequences to investigate the roles of species identification and sexual selection in the evolution and diversification of this unique genus of whales.

 

To learn more about the NEW species, Mesoplodon perrini, discovered in 2002 - see my PhD webpage at the University of Auckland

 

See The Beaked Whale Resource for more information about these strange whales.

 

At Dalhousie University, in Halifax, Nova Scotia on the eastern coast of Canada, I spent two years as a Killam Postdoctoral Fellow investigating population structure and gene flow in the northern bottlenose whale, Hyperoodon ampullatus. This is supposedly the least elusive and easiest to work with of all beaked whales. The small, resident population in the Gully (a submarine canyon on the Scotian Shelf near Sable Island) which has been studied for over a decade by Dr. Hal Whitehead's team at Dalhousie University was easy to find and skin biopsy samples were collected from a number of individuals using the PAXARMS system. We were less successful with the population off northern Labrador. Two summer field seasons (2003, 2004 - see photos via link below) yielded only a handful of sightings and three biopsy samples. Instead, teeth collected from animals taken by Norwegian whalers in this region in the late 1960's-early 1970's were used as a source of DNA. Genetic analyses based on 10 microsatellites and mitochondrial (mt) DNA control region sequences revealed the endangered Gully population to be highly distinct from animals off Labrador. The results from this work were recently accepted for publication in Molecular Ecology (April 2006). Further work to investigate social structure and epimeletic behaviour in bottlenose whales is still underway.

 

See also my old Dalhousie University PDF website

Have a look at our Labrador 2003 and 2004 FIELDWORK photos

For additional information about our 2003 field season, click here.

 

Other related projects in which I am also involved include:

 

DNA sequences can provide universal characters for taxonomic identification. There are three major uses of molecular taxonomy:

Together with Drs. Scott Baker, Howard Ross and Shane Lavery, I established DNA-SURVEILLANCE, an on-line program for the DNA identification of whales, dolphins and porpoises, as part of the Witness for Whales project (see below). This program is currently in the process of expanding to other taxa including seahorses, moths, prawns, HIV subtypes, biofilms etc. Check it out!

 

I have been involved in the Witness for Whales project for the molecular monitoring of whalemeat markets in Japan and Korea, coordinated by Dr. Scott Baker at the University of Auckland, since 1998. Much of this work was funded by the International Fund for Animal Welfare (IFAW). Findings of this work currently being prepared for publication include:

 

Cuvier's beaked whale, Ziphius cavirostris, is the most cosmopolitan beaked whale. Found in most of the world's oceans, this species has become the focus of widespread concern due to its susceptibility to the adverse effects of sound generated by navy sonar and seismic surveys. The US Marine Mammal Commission Beaked Whale Technical Workshop held in April 2004 highlighted a number of key knowledge gaps in relation to acoustic impacts on beaked whales. The Workshop recommended that studies be undertaken to define species and population structure, assess distribution and abundance, and investigate population trends in local areas. I aim to answer the first of these questions for Ziphius and identify units for conservation through mitochondrial DNA analysis of over > 200 specimens (most represented by skeletal material collected from strandings) from throughout the distribution of this species.

Click here for link to Ziphius FIELDWORK (museum visits etc) photos