West Williamston Egg Predation Survey – Week 4

A glorious morning, but where were the females?

David Redhead had already seen a female before my arrival at 10.00am.  With a mild east wind and glorious blue sky we felt sure that there would be egg laying around us in abundance.  It was not to be and they were all elsewhere(see below).

Count details are as follows
Outside the fence I had 11 new eggs including 1 set of triplets.  54 eggs were re-found including 8 sets of twins and one set of triplets, with 1 predation.  This makes a total of 65 eggs with one predated egg (66 tags).
Inside the fence David found 21 new eggs and re-found 48 eggs with 1 predation.  There were 7 doublets and 1 triplet.  This makes a total of 69 eggs with one predation (70 tags). 
The overall egg total is now 134, with 2 predated eggs. This total includes 3 sets of triplets and 15 doublets (or twins)               
One particular observation makes the whole study worthwhile.  We have often wondered whether females lay 2,3 and more eggs when they are laden with eggs e.g. after bad weather, or do these multiples occur because there is something about the site that is extremely attractive, resulting in different females laying the eggs. 
Last week twin eggs were tagged with white wool, and since then a third egg has appeared – now tagged with blue.  Had the white tags not been there these eggs would have been described as a triple when it clearly wasn’t - evidence that the location itself was the attraction.

Nor is counting ever boring.  We often find eggs laid in the six o clock position and today found one twig with 2 eggs laid around the same spine - one at twelve o clock and the other at six.  Nearby were triplets, twins and a single egg all found on the same twig within a five inches of each other.

And where were those females?  
At least 11 were seen by visitors all over the reserve (well before 1.00pm).  Then, on leaving, I was shown the above adult just a few metres from the car park, with 3 others nearby!  Could the connection be that they were by the hedge on the side sheltered from that ‘gentle’ east wind?

Nikki Anderson

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