Every single fish that the Dyfi ospreys catch, we record it.
Monty may have a sneaky one now and again when there are chicks present and he needs a little time away from the family, so we can't record these obviously, but we don't think there are many.
Ospreys throughout the world eat hundreds of different species at different location/nests, but there will usually be one fish species that is preferred over any other. At the Dyfi, that species is the grey mullet.
The grey mullet makes up approximately 50% of the osprey's diet with flounder making up around 20% and trout 25%. These ratios can change throughout the season but once averaged out over the season, and between seasons, there is remarkable consistency.
Over the years we have theorised that Monty may catch specific fish species dependent on environmental factors at the time such as tide phase, temperature, wind direction and so on. Three scientific studies have shown to date that there is no scientifically significant correlation between species caught and any of the environmental parameters we have measured! He seems to catch when he (or the family) is hungry, and whichever species he finds the first.
These charts are all from the 2015 season, but they look pretty similar each year.
Fish Stats for 2015
Fish Stats for 2014
With many thanks to volunteer Vicky King who makes these wonderful graphics for us from some boring looking data every week/year.