Bizkaiko Foru Aldundia - Diputación Foral de Bizkaia

Some species of animals take advantage of the waste. The rubbish that we generate is a valuable nutrient for some scavenging birds (ravens, crows, seagulls, etc.), which are very common in Bizkaia.

The species that feed on the rubbish in landfills can be divided into two groups:

1. Territorial species. These defend their territory from others of the same species, which means there can only be a small number of specimens. There is no problem with these are they are very small in number.
2. Non territorial or gregarious.These cohabit both with members of their own species and with those of others. Examples of these are seagulls and corvines.
   
   Their growth in numbers, due in part to the small number of predators, is sustainable from the environmental viewpoint.

   This increase may cause biological disturbances in nearby species and even in human beings.

Caption: 70% of the diet of seagulls
is made up of waste

The problem of the presence of seagulls on the Municipal Solid Waste landfills is global, ecological and is linked to the abundance of food there (Joan Carles Senar, researcher of the Zoological Museum of Barcelona and the author of several studies on seagulls). Seventy per cent of their diet is made up of waste.

In order to correct this spiralling increase towards biological disorder, it is necessary to eradicate the problem at its origins, which in this case is the possibility for these animals to find food on the landfill.

The intention is to get them to seek food once again from their natural resources, as they have done throughout history.

Seagulls cause serious problems for the daily management of the landfill (noise, excrement, the presence in the proximities of compacting equipment, their impact on the landscape), which also makes their removal recommendable.

Moreover, they represent a hazard for planes during taking off and landing at nearby airports.