Birds and the city: General patterns in urban Mexico

Background/Question/Methods

In the last few decades, the exponential growth of urban areas has become of major environmental concern worldwide, representing one of the major forces driving land-use change across the globe. Fast-growing human populations have resulted in a rapid expansion of urban areas and the creation of new cities, representing an important threat for biodiversity. Urban development is expected to increase importantly in less developed regions over the following decades. Ecologists have conducted research to assess the effects that urbanization has on wildlife communities; however, urban ecology knowledge is heavily biased towards research from temperate urban areas. Contrastingly, many large cities are located outside of these three regions, and given that the majority of future population growth is not expected to occur in temperate areas, there is a mismatch between the literature on urban birds and the regions with the most rapid current and future urban growth. Here I review some publications focused on urban birds in Mexico to set the current national knowledge into a global context and propose future research directions.

Results/Conclusions

Considering all tropical and sub-tropical countries, Mexico ranks 5^th (after Australia, Brazil, Argentina, and China) in the number of urban bird publications in journals. Most publications derived from research carried out in Mexico are bird lists and studies focused on bird communities and assessment of population/abundance variations. Most studies have been carried out in four cities: Mexico City, Morelia (Michoacán), Querétaro (Querétaro), Pachuca (Hidalgo), and most recently Xalapa (Veracruz). Although some ecological patterns are similar in relation to those reported for temperate areas, others differ. For example, urbanization tends to favor granivores and insectivores in Mexico, while omnivore, granivore, and cavity nesting species tend to be selected in temperate areas. Undoubtedly, urban ornithology is a growing discipline in a promising stage in Mexico. Thus, in order to understand how birds respond to urbanization in the country, future studies are needed to focus on a wider selection of human settlements, including large-, medium-, and small-sized urban settlements. Also, as suggested previously, ornithological studies in cities need to progress from descriptive to mechanistic. Such knowledge could generate important information to influence urban management and planning policies to enhance habitat quality for urban-dwelling wildlife and the environmental conditions Mexican citizens face on a daily basis.