This week I have mainly been counting. Wildlife surveys make up a reasonable percentage of our work on the island, and this week it was time for the islands largest survey; the annual gull count.
Every year since 1957 there has been a count of the nests belonging to the Lesser Black Backed Gulls on the island. That year there were 218 nests found on the island and the numbers have been increasing slowly since.
In order to count the gulls the island was split up into 5 areas, with each team assigned an area to check. The teams would then methodically make their way through their area marking and counting each nest that they come across. Any nests belonging to Herring Gulls were counted separately. After each team had finished counting a member of another team would then go into an area to find the error rate of the original counters. They would do this by looking at the first 100 nests they come across while taking a random path through the area. The number of unmarked nests in that 100 would then give you an error rate for that area and allow you to calculate a corrected total.
After nearly 4 hours among the gulls being swooped and pooed upon we finally concluded on a total of 3606 nests, considerably more than 1957! This number however is not a complete total as due to the rough sea conditions we were not able to count the gulls nesting on the cliffs from a boat as is the normal practice. Since the gulls are documented as being monogamous we can safely conclude that each nest required 2 gulls present on the island, so that gives you an idea of the number of gulls we have flying over our heads on a daily basis (7212)!
Other wildlife that we have counted this week have included slow worms and moths. We complete a slow worm survey on a monthly basis by lifting 20 slow worm sheets placed strategically around the island and counting the number of males, females and juveniles under each. Contrary to popular belief slow worms are not directly related to snakes, but are actually categorised as legless lizards. This month we found 9 males, 7 females and 2 juveniles.
For our moth survey we place a moth trap and a light outside overnight and collect it in the morning. Using small boxes with identification windows, we are able to identify the varieties of moth that have been collected and these are then recorded in a similar way to our other surveys.
Other than counting this week, Vicky and I have been busy building things out of driftwood that washes up on the beaches. Vicky is currently working on a bench which is coming along very well, and I am working on a bird table to offer a safe feeding area for some of the smaller birds on the island.
We have also had a scout group resident on the island over the weekend, and we have tried to show them what our job on the island is all about and get them involved in some of the work that we do. Most of them seemed to have a good time with the exception of a few that were rather disenchanted with living among a gull colony for obvious reasons!
"If you'd like to read this article again press 1, if you'd like to have a cup of tea press 2, or if you'd like to read this weeks news story about a mans obsession with call centre phone options click here:" http://www.bbc.co.uk/news/technology-22567656
See you all next week :)
Every year since 1957 there has been a count of the nests belonging to the Lesser Black Backed Gulls on the island. That year there were 218 nests found on the island and the numbers have been increasing slowly since.
Lesser Black Backed Gull with 2 eggs in the nest. They usually lay up to 3 per year
In order to count the gulls the island was split up into 5 areas, with each team assigned an area to check. The teams would then methodically make their way through their area marking and counting each nest that they come across. Any nests belonging to Herring Gulls were counted separately. After each team had finished counting a member of another team would then go into an area to find the error rate of the original counters. They would do this by looking at the first 100 nests they come across while taking a random path through the area. The number of unmarked nests in that 100 would then give you an error rate for that area and allow you to calculate a corrected total.
After nearly 4 hours among the gulls being swooped and pooed upon we finally concluded on a total of 3606 nests, considerably more than 1957! This number however is not a complete total as due to the rough sea conditions we were not able to count the gulls nesting on the cliffs from a boat as is the normal practice. Since the gulls are documented as being monogamous we can safely conclude that each nest required 2 gulls present on the island, so that gives you an idea of the number of gulls we have flying over our heads on a daily basis (7212)!
Other wildlife that we have counted this week have included slow worms and moths. We complete a slow worm survey on a monthly basis by lifting 20 slow worm sheets placed strategically around the island and counting the number of males, females and juveniles under each. Contrary to popular belief slow worms are not directly related to snakes, but are actually categorised as legless lizards. This month we found 9 males, 7 females and 2 juveniles.
Female slow worm from under the sheet in the background
For our moth survey we place a moth trap and a light outside overnight and collect it in the morning. Using small boxes with identification windows, we are able to identify the varieties of moth that have been collected and these are then recorded in a similar way to our other surveys.
Other than counting this week, Vicky and I have been busy building things out of driftwood that washes up on the beaches. Vicky is currently working on a bench which is coming along very well, and I am working on a bird table to offer a safe feeding area for some of the smaller birds on the island.
Vicky working on the frame of her bench
My bird table
We have also had a scout group resident on the island over the weekend, and we have tried to show them what our job on the island is all about and get them involved in some of the work that we do. Most of them seemed to have a good time with the exception of a few that were rather disenchanted with living among a gull colony for obvious reasons!
"If you'd like to read this article again press 1, if you'd like to have a cup of tea press 2, or if you'd like to read this weeks news story about a mans obsession with call centre phone options click here:" http://www.bbc.co.uk/news/technology-22567656
See you all next week :)
Nice to see the blog up and running so that we can follow life on Flat Holm Island !!!!!
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