One of the questions I was asked most during this year's goose breakfasts was - What time do the geese usually leave the Basin? I tried to explain to some of the visitors eager to see large skeins of geese flighting inland to feed, that there could be a number of reasons (not excuses!) why the geese were still just sitting there.
So in this Basin Notes I would like to go through some of the main factors that affect why the geese leave the basin at different times during the morning to fly inland to feed.
The first of these is how long these birds have to feed during the day. From their arrival during September until the end of British Summer time at the end of October, the geese can be feeding for anything between 12 to 16 hours a day.
Geese are primarily herbivores, eating mainly grass, cereals and sometime root vegetables, which have a nutritional value that is lower than animal foods. Also because geese have an inefficient digestive system to process this food they need to maximize their food intake, their strategy for doing this is basically to eat as much food can as often as they can.
This still doesn't explain why the geese are sometimes still sitting around on the mud in full daylight, when they could have been out feeding hours ago. This is where there is a problem with their 'eating as much as they can' strategy. Their food processing rate is slower than their food intake rate, or in other words their 'eyes are bigger then their bellies'! So when there are longer days (for feeding) and shorter nights (for food processing) the geese need to have a long lie in before they can fit their breakfast in!
As the days shorten and the nights get longer, this is when the geese start flighting out to feed at the crack of dawn, and will also extend their feeding by moving back out at night around the full moon period to feed in the fields again.
The weather can also play a large part in the feeding movements of the geese on the basin. During late winter as the temperature drops, cold and windy nights mean that the geese will expend large amounts of energy trying to keep themselves warm throughout the night as they roost on the mud or waters of the basin, this may also lead to the birds leaving their roost as early as possible to start feeding.
Extended periods of freezing or snowy weather can lead to large-scale movements of birds to and from the basin. Geese using inland water bodies, such as hill lochs or reservoirs as roosts, can struggle to find drinking water and their roosting sites become unsafe when frozen, as foxes are known to cross ice to reach roosting birds during the night. This is when the numbers of Greylag geese on the basin starts to increase.
Large falls of snow can also cause problems for feeding geese, especially if they are too deep or frozen, which make it impossible for the geese to scrape down to their food source below. Last winter was a good example of this, during the worse period of snow the weather programmes showed a satellite image of the whole of Scotland. This image showed the country as almost completely white except for a small green area in the southwest. The next morning driving through Arbroath the sky was full of skeins of geese crossing the Tay heading south, probably around 10,000. During the next week Solway Firth had record numbers of pink-footed geese, it was as if the geese had seen that satellite image and headed straight to the only place in Scotland not covered in two feet of snow!
So as you can see there are quite a few factors that affect what time the geese are going to leave the Basin for their breakfast. But one thing is certain, food is the main driving factor for our geese, as it becomes harder for them to find enough, they can just up and move to somewhere else where they can get enough food to have a lie in before breakfast again.
So there is no better time to get out to one of the hides on the reserve to watch the wonderful spectacle of large numbers of pink-footed geese leaving the basin to flight inland to feed.