Saturday, 6 April 2013

Cormorants on The One Show

Note: The programme will be broadcast on May 15th 2013 at 7 pm.
A late nesting cormorant, not yet in breeding plumage.
Do you remember the closing shots of "Jurassic Park"?  A pelican flew beneath the helicopter, looking like a pterodactyl to remind us that dinosaurs are not extinct; they are all around us. The Paxton pelicans are perhaps even more prehistoric-looking than those brown pelicans. I'm talking about cormorants of course.

We like our cormorants at Paxton Pits Nature Reserve. They are charismatic birds with loads of interesting features, such as feathers that soak up water rather than repelling it. This enables them sink and makes diving easier, but isn't that helpful when they need to fly!

Alex and Jeff
The breeding colony on the Heronry Lakes provides a lot of interest all year round because we see nesting birds from December onwards and then roosting birds when all the chicks have fledged. At the moment (in this leafless spring) you can spot over 60 bulky nests with a nice, fresh coat of "white-wash" and you can hear the clamour of the birds as they meet and greet. The general cacophony is swollen by the rattling bill-clapping of herons that live among the cormorants. Stand down-wind and you might also catch a whiff of fresh, fishy guano: Lovely!

If you had come here a few years ago you might have seen 180 nests, but the colony seems to be in decline, perhaps in a faster fall than the national trend, and we do not know why. Of course we can make guesses, but there probably is not one simple answer. Our colony started about the time that nearby Grafham Water was stocked with rainbow trout and so it has been suggested that wintering birds, including some from the continent, decided to stay and breed. Certainly, a lot of our cormorants do visit Grafham, so you can imagine that the anglers there aren't as fond of them as we are.
Launching time.

Rainbow trout are reared in densely stocked tanks and ponds, so when they are first released into a reservoir they stay in a tight shoal that attracts predators, both avian and human. It is possible to catch trout three-at-a-time on a fly rod when they are first stocked like this. The fishery people at Anglian Water have tried several strategies to avoid too much predation and too many parasites and at the same time make the fishing a bit more interesting. These techniques have included "trickle-stocking", where fish are introduced in smaller numbers, more often and at different locations round the lake, and recently, stocking with larger fish (over 2 lbs weight) that are twice the size that cormorants can easily catch and fly away with.  I think it works and it may be part of the reason why we have less cormorants now. Incidentally, the fish eventually disperse and become more like the real thing; mean, lean, wild and hard to catch.

The Angling Trust
The Nottingham-based Angling Trust has launched a national campaign to "cull" the cormorant population because they believe that fish stocks are declining all across the country and that it is largely because of the birds.  The Royal Society for the Protection of Birds (RSPB), of course, takes a different view saying that they accept that there are places where cormorants cause significant economic damage, such as trout farms, but that there is no case for the widespread shooting of birds away from such places. Both sides are eager to make their case loud and clear as our Government (DEFRA) considers whether to issue shooting licences or not.

Miranda and a log?
Here's my personal view:

I have no doubt that fish stocks, both coarse and game, are declining in many places but the causes are many and include pollution, disease, over-stocking, over extraction, over fishing and competition from introduced species such as American crayfish, European catfish, zander, mitten crabs, zebra mussels, killer shrimps and many more. Spawning habitat is ruined by siltation and the canalisation of rivers for navigation and the requirement to move flood water away as swiftly as possible. Fallen trees, rocks and other structures that would provide shelter for fish and allow the recruitment of young fish are removed from our rivers. Many freshwater fisheries are just big, featureless holes in the ground, filled with water and overstocked with farmed fish. There is no natural food in such places and the fish have to be fed like livestock. Critically, these fish have nowhere to hide. It can't all be the cormorant's fault.
Dave makes final adjustments. 

You can see that there are two sides to the argument and that it's not a simple Yes/No issue. Both sides will need to listen to and study the other's case. (See the links at the bottom of this entry).

This week, we played host to the BBC's "The One Show" in advance of a programme that will feature our cormorants  and the two main protagonists in the debate. Jeff Knott will represent the RSPB and Mark Lloyd will represent the Angling Trust.

It took all day, on possibly the coldest April Friday ever, to capture the interviews and the cormorants on camera, but luckily the sun shone and I think we got everything that was needed. The interviews were conducted by Miranda Krestovnikoff, who is well known as a wildlife broadcaster, but not famous for playing with toy boats. However, Dave Denny who was producing the film, seemed to know what he was doing when he produced what looked like an ivy covered log that turned out to have a battery powered speed-boat inside. It also had two cameras mounted on it; one on top and one underneath.

Mark Lloyd (from his blog).
The idea was for Miranda to launch it on the lake while Dave used the remote to guide it near to swimming cormorants. It worked brilliantly, except that there was only one cormorant on the water and he swam away. If there had been more cormorants in the water, it would have worked. A pair of swans and a pair of Canada geese both seemed interested in what we were doing and came over to have a look.

I suggested that an alternative shot would be to use the log-boat to film a fisherman from the cormorant's viewpoint. " Now that we have seen the angler from the cormorant's point of view, let's go over to Mark Lloyd who will give us an angler's view of a cormorant............."

I bet they don't use it,  but I can promise some good shots of Paxton Pits and the cormorants. We will have to wait a few weeks to see how well each side puts it's case, but I'll let you know as soon as I have a date for the show.

The crew from the One Show were:
  • Miranda Krestovnikoff (presenter).
  • Dave Denny (producer)
  • Alex Holden (camera)
RSPB Policy Unit :
  • Sarah Dove
  • Nik Shelton
  • Jeff Knott
The Anglers Federation was represented by their Chairman, Mark Lloyd.


RSPB and Cormorants look here. There is also a position statement on their website in the form of a letter to DEFRA.

The Angling Trust has a lively website and several blogs This is the most relevant page, from March this year. Angling Trust. 

Our own website has masses of detail on cormorants. Start here and follow links to get more information.