One of the most critical functions that birds have, and one many people tend not to think about or realize, is pollination. There is a reason the euphemism for reproduction is “the birds and the bees.” Just by the very act of landing on and feeding from plants, birds transfer pollen between the male and female reproductive organs of a flower, resulting in fertilization and the production of seeds.
Hummingbirds and sunbirds, for example, are essential pollinators for many plant tropical species, particularly those with red or orange flowers, which they are particularly attracted to (which is why so many hummer feeders have red flower shapes where the birds can suck up that sweet nectar). But even the humble European blue tit or chittering chickadee play their part when plucking seeds or insects from flowers, as the pollen gets trapped in their feathers and on their beaks, then spread around as they fly and land elsewhere.
Some birds like the Eurasian jay and Clark’s nutcracker actively bury seeds such as acorns and those from pine nuts as they stock up their winter stash during the fall; not all of those seeds will be found again, and new forests can grow in the space of a few years. Other birds of course eat seeds immediately as part of their diet and then distribute these across different areas through their droppings. This can mean the survival and growth of plant species in new areas, enhancing the diversity of plant life in ecosystems. Birds therefore also play a role in maintaining the genetic diversity of plant species.
Without birds, many plant species would not be able to reproduce, leading to a significant reduction in plant diversity and, consequently, a decrease in ecosystem health.
One major role birds play is controlling pests. Many bird species, such as predators like hawks and owls, feed on rodents and other small mammals, helping to control their populations. This is particularly important in agricultural environments where pests can cause significant damage leading to substantial economic loss as well as food availability for us. And it’s not just the furry squeaky pests – there are literally thousands of insects and other invertebrates that can reduce a healthy ecosystem to a shadow of its former self within days.
In recent years, owners of coffee plantations and vineyards have been listening to the studies and successfully incorporating bird nesting sites for those species that thrive on the specific pests that can destroy the coffee beans and vines. Also, by controlling pests, birds help to reduce the use of pesticides, which over decades of constant use in all habitats has had a devastating impact on many other species that are crucial to our environment.
Birds are also incredibly important in something called nutrient cycling: by eating insects and other small organisms and then excreting their waste, which contains essential nutrients such as nitrogen and phosphorus, these nutrients are then reincorporated into the earth, promoting the growth of plants and symbiotic fungi and lichens.
Studies have shown that it isn’t enough just to plant out a tree or shrub with some soil – there must be so many other goodies packed in the accompanying substrate as well, to help these plants establish their lifeforce-giving network under our feet. “Recycled” bird food is what the world needs: the Aztecs knew this and literally built their entire empire on seabird poop.
One aspect of birds that has been known for some time in mining situations is also how vital birds are at telling us something is wrong. Taking the “canary in the coalmine” phrase and applying it to the rest of the world can show us just how healthy an ecosystem is. Birds are remarkably sensitive to changes in their environment, and their population numbers can tell us a lot more than just how they are doing.
A sustained decline in bird populations can signal the degradation of habitat quality or the presence of environmental pollutants, so monitoring bird populations in any way possible can provide important information about our planet’s health and the need for conservation measures. Taking part in any local or national bird counts or simply submitting any sightings to eBird helps those scientists who collate these vast datasets work out where attention is needed and can often act in real-time before it’s too late.
The importance of birds to ecosystems and global biodiversity cannot be overstated. Unfortunately, many bird species are currently threatened with extinction due to human activities so immediate action and conservation is essential to ensure the survival of all the extant bird species.
By paying attention to how birds are doing and restoring their lost habitats, correctly regulating hunting policies and enforcing punishment for poaching, as well as us all playing our part in mitigating against climate change are absolutely essential to their continued existence – and at the same time, ours.