Nesting Pairs and Chicks Raised (2006-2017)

Here are the breeding results we have recorded in bar chart format.

Over the last 12 years the average number of breeding pairs has been about 17 and the number of chicks raised has been 59.

In 2017 the number of surviving chicks was much higher than average.  Even allowing for the fact there were more breeding pairs their success rate was above average. This would indicate that there was a big increase in vole population and therefore there was a plentiful food supply.

Average Number of Chicks per Pair (2006 - 2017)

This chart shows the average number of chicks raised by each pair.

The numbers range between 3.1 and 4.7 and the average is 3.5. In 2017 the average chicks per pair was a remarkable 4.7 which is a very high figure compared to previous years. Survival rates are always higher in those years when there is a plentiful supply of mice and voles. When prey populations are low then this will affect the survival rates of chicks. The reasons for variation in mice and vole populations is not well understood.

Another factor is the weather. Owls need dry and quiet conditions in order to hunt. Wet and windy conditions usually means that hunting success falls to nearly zero. Extended periods of wet and windy weather will increase chick mortality rates.