Friday, June 08, 2007
Great Cormorant Breeding
Over the weekend I made an early morning start to look at Gould's Lagoon. As I neared 'Gould's", I realised that the lagoon would be covered in an early morning fog and diverted to the nearby Derwent Marshes. As I drove towards the Bridgewater Bridge from Granton, I noted a flurry of activity over the water and pulled off to investigate. Almost immediately I spotted a White-breasted Sea Eagle being noisily pursued by 2 Kelp Gulls. Thinking that this might prove to be a photo op. as the eagle was getting ever closer, I took my eyes off the action to pick up my camera. This proved to be a mistake because when I looked back, no eagle! I got out of my car and scanned the area with my binoculars. The conditions were very still with low sun penetrating the thin mist over the water. While scanning, I noted a number of cormorants on an old river washed tree that had grounded in the shallows several hundred metres away. As I looked more closely, I realised that there were several Great Cormorants nests, some with sitting birds (see photo). It's not that unusual for them to breed in the Winter months, and I've recorded them doing so in the Derwent Marshes before. I assume that the timing of their breeding is tied to the availability of suitable food resources. I have seen a general increase in the numbers of Great Cormorants around the Hobart area recently, many of them immature birds. Just as I was getting back into the car, the Sea Eagle reappeared, floated across the water, picked up something off the surface and flew back. Never quite close enough to get the sort of shot I was after, I took a shot anyway, as you can see. This time I kept my eyes on it. It alighted in a large pine tree on the river bank overlooking the marsh and it then became clear that this is where it had 'disappeared' to earlier. Interestingly, although the eagle flew close to the cormorants, they seemed unfazed. This probably indicates that they're sitting on eggs, as I imagine there might be a different reaction from them if they had young.