Horseshoe crabs and knots in Delaware Bay, USA


This video from the USA is called Delaware Bay Shorebird Project.

By Nigel Clark, of the British Trust for Ornithology, in Thetford, England:

Getting to the Arctic on time: Horseshoe Crabs and Knot in Delaware Bay

Arctic breeding waders are often constrained by the availability of resources at stop over sites on their northward migration to the breeding grounds. These constraints become most acute at their last stopover before they reach the breeding grounds as late arrival, or arrival in poor condition, may lead to a reduction in breeding productivity and subsequent survival.

The situation in Delaware Bay, USA is particularly difficult for migrating waders, as they depend largely on the eggs of Horseshoe Crabs that are exposed on the beach surface. These surface eggs are abundant only when there are extremely large numbers of breeding crabs. In the early 1990’s there was a dramatic increase in the Horseshoe Crab fishery which lead to a major reduction in spawning crab numbers. This resulted in a reduction in the rate of weight gain of migrating waders, particularly Knot, and coincided with a dramatic decline in the population.

Initial responses of the conservation community were to call for a permanent ban on Horseshoe Crab fishing which lead to the imposition of harvest quotas, and in some States a complete moratorium. The first signs of a recovery in the Horseshoe Crab population are beginning to appear, which has in turn lead to the call from fishing interests for increases in fishing quotas. The conservation community had been collecting extensive ecological data over a decade which proved the link between food supplies and the condition of the birds but this is not easy to explain to non-scientists. The way forward was found after many days of discussions between all parties. The result is an Adaptive Resource Management approach and gives hope for the future of the Horseshoe Crabs and Knot.

Great tit attacks insect hotel, video


In this video, a great tit has found out how to catch the insects hidden in the back of the insect hotel. Maybe more glue should have been used in making the insect hotel?

Melchior van Tweel made this video in his garden in the Netherlands.

Dutch crane flies having a good year


This video says about itself:

Large Crane Flies Mating

20 January 2014

The Crane Fly has a number of different nicknames around the world including mosquito eater and gallinipper. There are over 4,000 different species of crane fly in the world that have been identified at this time, making them the largest family within their genus. The winged adult crane flies usually do not eat, and spend their brief time mating and laying eggs.

Dutch entomologists report (translated):

Sunday, November 23, 2014

Because of the very favourable weather conditions this year leatherjackets, the larvae of crane flies, are already strikingly large and come with hundreds of specimens per square meter in grasslands. 2014 is the fifth year in a row with many crane fly larvae. Various birds will benefit in the coming time.

At present, especially the leatherjackets of the European crane fly (Tipula paludosa) and Tipula oleracea can be found easily.

Blue ‘black’ squat lobster discovery


This video is about diving in the Oosterschelde estuary in the Netherlands. Animals seen include a normally coloured black squat lobster.

Dutch marine biologists of Stichting ANEMOON report on Sunday 23 November 2014:

Recreational divers have found in 2013 and 2014 two bright blue coloured black squat lobsters in the Oosterschelde. The normal colour of these crustaceans is orange to dark red. Only one in two million animals have this rare blue colour deviation. The fact that two have been detected in our coastal waters shows that the population of squat lobsters is locally very high.

See also here.

Blue black squat lobster, 18 August 2013 (photo: Arne Kuilman)

Lobster molting, video


This is a video about a European lobster in the Oosterschelde estuary in the Netherlands.

When lobsters grow, their old shells become too narrow. So, they have to molt; and emerge, as the video shows, from their old shell with their new shell.

Rob Dekker made the video.