Each year the Spey Fishery Board and Foundation staff complete three bird counts on the river. Counts are scheduled for Mar/May/December although in the past more frequent counts have been undertaken. The main species counted are goosander, merganser, cormorant, heron and goldeneye. Heron counts are mainly for interest whilst the goldeneye counts are to provide count data to other interested organisations.
The counts nowadays are completed from Aviemore downstream either by canoeing or by drive and walking, the method chosen depending on the weather, river conditions and the staff availability. The information collected during the counts is used to support the application for the sawbill licence which permits licence carriers to scare or control birds, by shooting if necessary.
The results for the March and May 2013 counts are shown below. The river is split into 10km sections e.g. the 110 section being the upper most counted section – above Boat of Garten, the 70 section between Castle Grant 3 and Advie Bridge and the 10 section 10 being downstream of Fochabers.
The results are shown as graphical form below:
The total numbers counted during the March count were Goosander = 56, Merganser = 13, Cormorant = 12, Heron = 5 & Goldeneye = 167.
The total numbers counted during the May count were: Goosanders = 33, Merganser = 2, Cormorant = 0, Heron = 3 & Goldeneye = 48.
It can be seen from these two counts that the numbers of birds on the river varies considerably. This variation can occur on a daily basis depending on factors such as the Spey river height, neighbouring river levels, presence of ice and inshore sea conditions.
The total counts for all species declined during the May count. Some of the birds could have migrated away from the area, be sitting on nests or moved upriver or into the tributaries to nest and rear broods.
In general the goosanders are normally more abundant in the lower river whilst mergansers are usually found around the Grantown area. Likewise more cormorant are usually found in the upper reaches as are the goldeneye which can be seen in great abundance upstream of Grantown on some occasions.
Four of these birds are primarily fish eating birds, although herons are quite adaptable and will even prey on ducklings. In a river like the Spey the most abundant and most readily available prey will be juvenile salmon with trout and eels secondary. The sawbills generally take smaller prey whereas cormorants are capable of swallowing a decent sea trout, small grilse or even a kelt. Goldeneye appear to feed on river invertebrates for which they must grub about on the riverbed?
I myself haven’t yet done an analysis of trends in fish eating bird numbers on the river but we do appear to have a healthy population!