Friday, September 16, 2011

The wind finally abated, albeit briefly, and allowed for the first Risso's Dolphin monitoring trip of the year to head out on calm seas. The aim was to photograph as many dorsal fins as possible to help with an ongoing photo-monitoring project. Because Risso's are usually an offshore species, virtually nothing is known about their population structure or movements. We are lucky enough to have good numbers off the Island at this time of year but exactly why they are here is uncertain; many young pups and juveniles have been seen over the years suggesting that the area may be an important nursery ground. Learning about site fidelity and trying to calculate how many individuals are using the area is vital to successful conservation and so photo-monitoring has been conducted since the 1990s to try and recognise individuals.

Although it was dorsal fins we were really after, the chance to photograph these amazing creatures leaping out of the water couldn't be missed! Adult Risso's reach up to 4m in length so they can make quite a splash. (c) Richard Brown

Risso's are relatively easy to identify as individuals as their dorsals accumulate scars and notches as they age. The dolphins are very social animals and it is thought that it is the animals themselves which mark each other during social interactions. Perhaps their prey also inflicts some of the marks. It is by recognising individuals that we will learn more about these amazing creatures. For instance two adults seen in 1997 were seen together again in 2006 and in 2009 an animal photographed in the English Channel was a perfect match for one photographed from here in 2006. (c) Richard Brown

We watched over 20 animals for a couple of hours, but it felt more like a couple of minutes. The dolphins were probably feeding and journeying for most of the time we were with them but sometimes it felt like they were just taking a look to see what we were up to. (c) Richard Brown

5 comments:

  1. These are so fantastic!
    All your photos make me immensely jealous :)
    Missing you x

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  2. I just love that first image - fabulous!

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  3. Brilliant photos!! Hope you managed to ID a few of them! Rissos are such crazy lookin creatures! Great blog, keep it comin!

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