An ecosystem service is any beneficial impact that nature provides to human society (The National Wildlife Federation, 2021). The concept was developed to describe the many benefits that a harmoniously balanced natural world brings to our societies and how neglecting the environment has negative consequences for human wellbeing (Jax, et al., 2013). A world with strong, healthy ecosystems allows us to have diverse food products, a stronger economy, and make advancements in medicine (The National Wildlife Federation, 2021). This is one of the key reasons that biodiversity conservation is so critical.
Ecosystem services can be split into four categories, identified by The Millennium Ecosystem Assessment (MA), 2003 (The National Wildlife Federation, 2021) (World Health Organization, 2003).
There is considerable debate on ecosystem services. The biggest issues include how to avoid double counting a process and how to incorporate ecosystem valuation into policy, land-use, and wildlife conservation decisions (Wenny, et al., 2011).
Birds occur in nearly all habitats around the world, respond rapidly to environmental change, and fill many ecological niches. They are highly mobile and therefore their activity creates links both within and between ecosystems (Wenny, et al., 2011). Migratory species link ecosystem processes that are separated by huge distances (Whelan, Wenny, & Marquis, 2008).
Birds play many roles in ecosystems: pollinators, seed dispersers, predators, scavengers, and ecosystem engineers (Whelan, Wenny, & Marquis, 2008).The ecosystem services provided by birds are often indirect and support or enhance other services, examples would be pollination, seed dispersal, and nutrient cycling which benefit plants. These plants then produce oxygen, food, timber, medicine, flood and erosion control, and recreation opportunities for humans (Wenny, et al., 2011). Many of the ecosystem services birds provide result from foraging. Through foraging, birds act as mobile links that transfer energy both within and among ecosystems, and thus contribute to ecosystem function and resilience (Wenny, et al., 2011).
Birds provide pest control regulation ecosystem services through foraging (Michel, Whelan, & Verutes, 2020). Birds consuming invertebrates reduces herbivorous insect populations, and plants can respond with increased growth and yields. For example, the attempt to remove Eurasian Tree Sparrows, Passermontanus, from China in the 1950s lead to insect pest outbreaks, which showed that sparrows indirectly benefited rice crops by removing pests (Wenny, et al., 2011). Additionally, the predator-prey interactions of raptors (suchas owls and hawks) hunting rodents can have economic benefits. Studies show that artificial perches attract birds of prey, which may enhance or concentrate foraging for rodents in ways that are beneficial to humans (Wenny, et al., 2011). Birds can exert strong top-down effects on food webs, which can result in prey population regulation, pest control, and corresponding changes in plant communities. Therefore, in the context of ecosystem services, population decline among birds may lead to changes that cascade through ecosystems and cause subsequent declines in benefits to humans (Wenny, et al., 2011).
Regulation services provided by birds, such as seed dispersal and pollination, are key ecosystem services (Michel, Whelan, & Verutes, 2020). Nearly 33% of bird species disperse seeds, usually through fruit consumption. Birds disperse the seeds of many woody plant species that have direct value to humans for timber, medicine, food, or other uses. Pollination relationships between birds and plants tend to be more specialized than with seed dispersal. Bird-pollinated plants are often more limited by pollen than by dispersal; thus, the effects of mutualism breakdown may be greater and faster-acting for bird-pollination than for seed-dispersal systems. However, where pollination is primarily by insects, seed dispersal is probably the mutualism more at risk (Wenny, et al., 2011).
Vultures are especially well known for scavenging, but many other species also scavenge including raptors, seabirds, gulls, herons, rails, shorebirds, woodpeckers, and passerines. By scavenging, carnivorous vertebrates contribute to regulation ecosystem services such as waste removal, disease regulation, and nutrient cycling (Michel, Whelan, & Verutes, 2020). Seabirds often nest in dense colonies in coastal areas and islands, and due to this they transport nutrients from the aquatic zone to the terrestrial zone. This is a key supporting ecosystem service that birds provide; by transporting nutrients in high volumes, they can influence the structure and composition of plant communities (Wenny, et al., 2011) (Michel, Whelan, & Verutes, 2020).
Ecosystem engineering is an service provided by birds from constructing nests that are later used by other species. Open-cup and domed nests are often taken over by small mammals, spiders, and bumble bees. The ground nests of tropical ovenbirds are used by beetles, social wasps, rodents, lizards, snakes, frogs, and even other birds. Woodpecker cavities are used by birds, mammals, amphibians, and arthropods. Nest burrows created by penguins, seabirds, alcids, parrots, owls, kingfishers, and passerines alter soil properties and affect nutrient cycling. They are also used by other taxa, including birds, snakes, mammals, and amphibians (Wenny, et al., 2011).
Birds supply provisioning ecosystem services in the form of physical products that humans use. Birds’ meat and eggs are used for food and feathers are used as filling for down duvets, pillows, and coats. Additionally, birds’ bodies and feathers are sometimes used for ornamentation (Michel, Whelan, & Verutes, 2020).
Birds provide cultural ecosystem services as sources of recreation including birdwatching and hunting, as pets, as well as through inspiring photography, art, and religious customs (Michel, Whelan, & Verutes, 2020). Cities are often where we come into contact with the natural world: in parks, urban nature reserves, and residential yards. You can look out of a window almost anywhere and see a bird; perhaps one of the most important services birds provide in cities is to be a reminder of the link between urban environments and the broader environment (Belaire, Westphal, Whelan, & Minor, 2015).
Birds are important to human society for a multitude of reasons; those which we see and acknowledge and those that we don’t. Controlling pests, pollinating plants, distributing seeds, and recycling nutrients are all services that birds carry out that help plants. Birds provide us with eggs, meat, and feathers to use in products. The nests that birds create are key parts of the lifecycles of other wildlife. Birds help us to connect with nature on a daily basis, from glancing out the window to viewing art that they inspired.
Bird conservation is important not just for the sake of biodiversity, but for the sake of human life. We could not exist, or at the very least live the same lives that we do now, without birds and the ecosystem services they provide.
Belaire, J. A., Westphal, L. M., Whelan, C. J., & Minor, E. S. (2015). Urban residents' perceptions of birds in the neighborhood: Biodiversity, cultural ecosystem services, and disservices. The Condor, 117(2), 192-202.
Jax, K., Barton, D., Chan, K., de Groof, R., Doyle, U., Eser, U., & Gorg, C. (2013). Ecosystem services and ethics. Ecological Economics, 93, 260-268.
Michel, N. L., Whelan, C. J., & Verutes, G. M. (2020). Ecosystem services provided by Neotropical birds. The Condor, 122(3), 1-21.
The National Wildlife Federation. (2021). Ecosystem Services. Retrieved from The National Wildlife Federation: https://www.nwf.org/Educational-Resources/Wildlife-Guide/Understanding-Conservation/Ecosystem-Services
Wenny, D. G., Devault, T. L., Johnson, M. D., Kelly, D., Sekercioglu, C. H., Tomback, D. F., & Whelan, C. J. (2011). The Need to Quantify Ecosystem Services Provided By Birds. The Auk, 128(1), 1-14.
Whelan, C. J., Wenny, D. G., & Marquis, R. J. (2008). Ecosystem services provided by birds. Annals of the New York Academy of Sciences, 25-60.
World Health Organisation. (2003). Ecosystems and Human Well-being: A Framework for Assessment. Washington, D.C.: Millenium Ecosystem Assessment.