Bureau Waardenburg
Varkensmarkt 9
4101 CK Culemborg
the Netherlands
T: +31 (0) 345 512710
email buwa


Population models

In a changing environment, it is important to assess the potential impact on the populations of birds or other species. For example, changes in food availability, number of breeding locations or the amount of toxins in the environment can influence survival or reproduction. Furthermore, human-related factors such as the construction of a wind farm can lead to bird mortality as a result of collisions.

We carry out many effect studies to assess the potential effect of developments or management measures on species or animal groups. As a first step, the consequences for reproduction and/or mortality are estimated. Then we can test whether these will affect the population. Effects at the population level can be investigated through population models such as matrix models.

Matrix models

In matrix models, the population is divided into classes based on age categories or stages (e.g. juvenile, adult). In the example below, this species is mature from the age of 4 years onwards, from which it can reproduce. Based on age-specific survival and reproduction, the change in the number of individuals per class can be predicted. In this way, the course of the population for a scenario with current survival and reproduction ('null scenario') can be compared with the population of an impacted scenario in which mortality and/or reproduction are affected.

Using this method, we have already produced population models for, guillemot, puffin, lesser black-backed gull, gannet and several other species.