West Williamston Egg Predation Survey – blog no 9 mid November 2014

The big miss-hap, or ‘accidents do happen’
Before the cut …………..
After the cut .....................
Our study site at West Williamston was divided into 2 halves ….. one - an area outside the electric fence consisting of the youngest blackthorn and surveyed (after the first two weeks) by me, and the other - the area between the electric fence and the field boundary - surveyed by David (Redhead) and consisting of 1 to 3 year old blackthorn much denser in nature.

Shortly after the eighth survey session the grass in the Reserve’s top field (where our survey was taking place) was cut as part of planned management. Unfortunately the contractor failed to see the tags marking very young blackthorn in the field on the outer side of the electric fence.  The tags, eggs and blackthorn were almost all lost (eggs right under the fence fortunately avoided the chop).
This was a bit of a disaster from the ‘overwintering egg predation’ survey’s point of view – or my half of it.  David’s half remains safe and intact being located inside the electric fence between it and the tree-line fence.
 On the other hand I have eight satisfying and illuminating week’s worth of data including recounts, recording, and the dates new eggs were found.  The most interesting outcome to me was establishing that eggs found in a ‘triple’ were laid as a pair and then added to days later.  This indicates that there was something special about that particular spot – the small bush was surrounded  by extensive  blackthorn that appeared to be just as suitable in every way.
The study will continue thanks to David’s commitment, his half of the site being intact. 
David has continued his counts into November and from now on the eggs will be re-found between now and the end of April to show which months the greatest predation takes place.


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