The Seagull Rain Dance

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Large Aberdonian Seagulls found near the beach

nyone who lives in or has visited Aberdeen has experienced the vast numbers of seagulls in the city. Many have encountered their wrath, whether it is stealing your sandwich or dive bombing you whilst walking along the beach. Being on the coast Aberdeen is inundated with rather large and confident seagulls even within the city centre. The gulls found on the shores are the European Herring gull. Although seagulls are mostly found along the coasts they have adapted to city life. These gulls are often found to be scavengers, rummaging through bins and land fill sites.

Seagull carrying out the "Rain Dance"

Although seagulls will predominately feed on seafood they are also capable of finding sources of food inland for example worms. Seagulls have behavioural adaptations which allow them to satisfy their carnivorous diet whilst inland. Aberdeen being a rather rainy place, seagulls use this to their advantage and are able to imitate the rain. The seagulls can be observed “dancing” and stamping their feet on grassy areas by raising and lowering each foot in turn. The movement of their feet on the grass causes vibrations which are similar to that created by rain. The vibrations cause worms to move to the surface believing it is raining. This rhythmic beat is repeated, the gulls can then be observed scrutinising the ground waiting for their easy snack to emerge.

Nikolaas Tinbergen was a Dutch ethologist and ornithologist whose work in animal behaviour earned him a Nobel Prize. Tinbergens four questions that are asked of any animal behaviour can be applied to the observed behaviour of the seagull dance. His theory states that every behaviour has a cause, development, evolution and function. The cause of this “dancing” behaviour could be attributed to periods of rain in which the seagulls can take advantage. The dance is a learned trick to coax worms to the surface. Earthworms stay underground unless flooded out by rainwater. The vibrations sent into the ground resemble that of rain or an approaching mole. The seagull dance is a taught behaviour and develops with age. The elder seagulls can be seen teaching young the padding motion on grass. The dance is therefore a learned or possibly inherited behaviour. Environmental factors play a role in the dance as it is more commonly seen in birds which have to supplement their diet or have moved inland away from the coast. The rain dance is used by other bird species also, for example similar tactics can be observed in thrushes.

The evolution of this behaviour using the land to obtain a food source could be sited to the origins of seagulls. If assumptions are correct that seagulls originated in moor lands as oppose to the marine environment they currently inhabit, this could be a plausible explanation for the possession of the grass dance. The moor environment would be wet and boggy allowing for successful use of rain mimicking. The rain “dance” is clearly an advantageous adaptation aiding in the survival by supplying the gulls with a tasty bite. Members of the flock are able to work together carrying out the padding action to enhance the success of the action and enable them to gain higher levels of worms.

The grass dance demonstrates how gulls are able to exploit the intrinsic behaviour of the earthworm to their advantage. The rain dance is clearly a beneficial behaviour as it helps the gulls to adapt to other ways of life away from the coast supplementing their scavenger diet.