Data from the the recent Birdwatch Ireland Garden Bird Survey shows the distances that some common garden birds travel before arriving to our Irish gardens. Influxes of birds arrive in Ireland during the winter period and it is very interesting to see where these individuals may have travelled from. In most cases, birds remain within a small radius of their nest during the breeding season. However, during the winter season some species can travel further distances.
Most small garden birds will not travel very far from home such as the Blue Tit, Great Tit and Coal Tit. Only after becoming independent from their parents will some birds disperse up to 20km away. As they become adults, they will travel less as they claim their own territories. These adults will usually stay within a 1-2km radius and rarely travel further than 5km away. Interestingly, large raptor species which prey on these garden birds will also stay within these small territories, if a sufficient amount or prey is readily available. Some interesting movements of sparrowhawk have been recorded such as an individual moving from Wexford to Cork and some birds have seemingly come in from the UK in winter.
The general consensus is that if a bird is lucky enough to have fledged in an area that meets all of its ecological needs, there is no need for the individual to venture far away.
Some species show very interesting migration patterns. While the birds recorded in Ireland during the breeding season are most likely the birds also found here in winter, the birds we see here in during the winter may have arrived from lands much further away such as Russia. Thanks to an extensive amount of Volunteer and professional bird ringing organised by the British Trust for Ornithology (BTO) we can now see maps showing some impressive examples of birds travelling large distances to and from Ireland e.g. the European Starling.
Understanding the different migration patterns of our various bird species can be very interesting. It is also extremely important for ornithologists and ecologist alike to know where different species have arrived from and how far they are capable of travelling. This tells us a great deal about the ecology of different bird species, ultimately helping us to answer important ecological questions such as why certain species will the expend the energy to travel long distances to Ireland.