Bumblebee Walk in
Birch Grove Wood 2015/16
For the last two
years, 2015/16 we have been monitoring the bumblebee population
around the meadow and in the lower part of Birch Grove Wood. This
survey method is set up be the Bumblebee Conservation Trust and the
data is collated nationally.
Walking the same
route every month we record how many and which species of bumblebees
are present. Sometimes identifying bumblebees is not straightforward
but with a bit of practice the main ones and be recognised by their
colouring and banding on the thorax.
Here are some
numbers for the last two years:
Some statistics to
evaluate the numbers:
| 2015 | 2016 | Totals | Expected F | x2 | 0.01 | 0.05 | |
| Common Carder | 40 | 14 | 54 | 27 | 6.26 | Significant | Not Significant |
| Buff Tail | 6 | 11 | 17 | 8.5 | 0.74 | Not Significant | Not Significant |
| Early | 1 | 2 | 3 | 1.5 | 0.17 | Not Significant | Not Significant |
| Red Tail | 10 | 45 | 55 | 27.5 | 11.14 | Significant | Significant |
| Garden | 8 | 3 | 11 | 5.5 | 1.14 | Not Significant | Not Significant |
| Tree | 3 | 4 | 7 | 3.5 | 0.07 | Not Significant | Not Significant |
| Honey | 25 | 25 | 50 | 25 | 0.00 | Not Significant | Not Significant |
| Unidentified | 19 | 22 | 41 | 20.5 | 0.11 | Not Significant | Not Significant |
| SUM | 112 | 126 | 238 | 119 | 0.41 | Not Significant | Not Significant |
The difference in
total numbers observed are only significantly different at a both
levels of significance for the Red Tail bumblebee for those two
years. There were significantly more Red Tails counted in 2016.
Common Carders numbers are also significantly different at a higher
level of significance.
There was no
significant difference in total numbers of bumblebees observed,
although in 2016 there were very no counts of any bumblebees in April
and May.
After a wet start to
2017, the bumblebee queens were observed in the Gardens in the middle
of March. Time to start up the bee walk again.
