Gary Keesing, of Levin, asks :-
In feeding birds I throw a handfull of wholemeal breadcrumbs onto the lawn. By chance the crumbs landed inside a long loop made by my garden hose. The birds wouldn't come too close. After observing them for two hours I shifted the hose and they fed on the crumbs. Why the hesitancy? Were they programmed to regard the hose as a snake?
Helen Taylor, a conservation geneticist at the University of Otago, responded.
What youâ€™re describing here sounds like neophobia (a wariness of new things); a common reaction in a wide variety of animal species. Avoiding new objects makes sense for avoiding danger, but not all species and individuals are as neophobic as others. Birds that live in complex habitats and encounter new things more often are likely to be less wary of new stuff than birds who live in very uniform, stable habitats. Some studies have suggested that urban birds are more used to dealing with new objects than non-urban birds, and so are less cautious around these new objects. You could do a fun experiment by leaving the hose down with the food inside the loop and seeing whether certain species of birds ventured inside the loop rather than others and how long it took them.
The opposite of neophobia is neophilia, and New Zealand has a great example of a neophilic bird in the kea. Kea are famous for tearing apart cars (and other things) and this is because they are extremely neophilic and love exploring and investigating new things. How did kea become so neophilic when neophobia seems much safer? The current thinking is that the lack of predators of kea in New Zealand would have allowed them to be neophilic with relatively low risk. Unfortunately, today, their neophilic nature often brings kea into conflict with humans.
Itâ€™s highly unlikely that the birds in your garden viewed the hose as a snake, because there are no snakes in New Zealand. However, this does raise an interesting point regarding whether a fear of certain predators is innate (pre-programmed) or can be learned, and whether that fear can be passed down through generations. This is particularly important in New Zealand where native birds evolved in the absence of mammalian predators and so are naÃ¯ve to the threat they pose (and thus tend to get eaten). If it was possible to expose adult birds to the threat of mammalian predation and have their new neophobic response passed down to their offspring, it could save many individuals. Unfortunately, research on New Zealandâ€™s South Island robins suggests that this species at least loses any fear of mammalian predators after just one generation of being predator free. This means that birds in sanctuaries or on predator free islands would be very vulnerable if re-invasion by mammalian predators occurred.
Feeding bread to birds may not be the best idea for their healt as it doesnâ€™t give them the nutrients they need. landcareresearch.co.nz have some excellent resources on choosing the best food for the birds. By providing different foods, you can attract an even wider variety of birds into your garden.
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