Urban ducks, to feed or not to feed?
The feeding of wildlife has always been a popular pastime, there are some steps you can take to minimise the ecological impact.
Article by Adelina Haluska, work experience student, University of the Sunshine Coast
The feeding of wildlife has always been a popular pastime, with the most enjoyable activity (in my opinion of course) involving feeding the ducks at the local lake with the kids squealing in delight. Although we know that feeding wild animals can potentially be detrimental to their health and behaviour it seems that when it comes to ducks most people treat them as a domesticated animal and forget that they are in fact wild.
A study led by Dr Darryl Jones estimated that up to 57% of Australian households participate in feeding wild birds, either through placing bird feeders within private properties or by feeding ducks on public lands. We can feel compelled to do this for a multitude of reasons. It can be just for the simple pleasure of attracting and having wildlife nearby, or a sense of helping bird species as urban sprawl reduces their foraging grounds (though in saying that, urbanisation can increase populations of some adaptable species, such as ducks living within urban waterways). Other people might attract birds to use as an educational tool, using the experience to teach the younger generation about interacting with local bird species.
The 2 most common species of ducks we tend to feed here on the Sunshine Coast are the pacific black duck (Anas superciliosa) and the Australian wood duck (Chenonetta jubata). Their diet is mainly vegetarian however they have been known to consume insects and molluscs on occasion. They forage by dabbling, a process where the bird will appear to dive down to find food whilst keeping their rear end above the water line, pointing it towards the sky.
One study of duck feeding at public ponds found bread to be the most common offering to ducks, with almost 5 slices of bread handed out per feeding session. This isn’t to say that all the bread was consumed, rather a large proportion is left uneaten and decomposes on the bottom of the lake.
The addition of bread, whether consumed or not, adds to the phosphorus levels of the water body which is thought to play a role in increasing the levels of soil bacteria responsible for avian botulism. Ducks that do consume bread are also at greater risk of malnutrition, disease, and other health risks due to the nutrient composition (or lack there-of) of bread. The introduction of additional food may also increase duck populations and alter the natural behaviour of ducks, promoting aggression amongst each other and towards us as they fight for food.
Concern is often raised that ducks may become dependent on us as a source of food as the increase in duck population alters the local food web, rendering natural food sources insufficient in maintaining a balanced equilibrium. While these concerns can be valid in some circumstances, current research has shown ducks spend most of their time foraging for natural food sources. One study noted that when bread feeding did occur that it had little impact on the time spent naturally foraging, and that certain individual ducks may drive others away to keep the bread to themselves.
Ideally, it would be better not to feed wild ducks. However, if you choose to feed there are some steps you can take to ensure that you minimise ecological impact:
- only feed appropriate foods such as cut grapes, cooked rice, bird seed or grains, frozen peas or corn once thawed, meal worms or commercial duck food pellet
- avoid bread or any kind of baked goods.
Finally, the most important rule, stop feeding when the ducks stop eating to prevent excess organic material decaying within the waterway. By thinking about the consequences of our actions we can reduce the impact we may have on ecosystems whilst still enjoying them for generations to come.
References
- Chapman, R. and Jones, D.N., 2011. Foraging by native and domestic ducks in urban lakes: behavioural implications of all that bread. Corella, 35, pp.101-106
- Chapman, R. and Jones, D.N., 2009. Just feeding the ducks: quantifying a common wildlife-human interaction. Sunbird: Journal of the Queensland Ornithological Society, The, 39(2), p.19
- Jones, D.N. and James Reynolds, S., 2008. Feeding birds in our towns and cities: a global research opportunity. Journal of avian biology, 39(3), pp.265-271.