This seems like an unanswerable question; one could say it’s in the eye of the beholder, but there are definite economic and ecological benefits to having birds in our world. This sort of question can be applied to any living thing on this earth, including us. The most reasonable answer is that they exist and are here for a purpose, whether we ever know what that is or not. But in our world, things have to have a purpose and if it can be shown to have financial value, it is considered even more worthy.
There many areas of purpose that can be ascribed to birds; providing us with food, clothing, or even fertilizer (guano); natural control for pests of all kinds, pollinators, seed dispersers, clean-up duty (scavenging dead animals), recycling nutrients, entertainment, and serving as models for art and religion. Not a great many of these have been seriously studied to determine their economic or ecosystem values, but without doubt they contribute to the overall world’s GDP.
Looking at just a few of these services provides great insight into their critical contributions to our lives. Take for instance, the ability to spread seeds and aid in pollination. The former may be their greatest function, especially in tropical forests where birds are known to spread the seeds of up to 92% of all tree and other woody species. This includes trees used for timber, edible and medicinal plants, as well as ornamentals.
The African mahogany trees especially depend on large birds (Hornbills and Currasows) that eat their fruits and then through the digestive process spread the seed. Here in the United States it is well known that Blue
Jays collect acorns and bury them for future feasting, but never recover all they bury and so new oak forests grow. Their relatives, the Clark’s Nutcracker, spread the seeds of the whitebark pine throughout the western U.S. If we were to have to replace the Nutcrackers with human workers and nurseries, a professor of Forest Ecology at the University of Colorado estimated the cost to be 11 to 13 billion dollars.
While pollination by birds is less than by insects, they are known to serve this purpose, especially in Australia, Oceania and in the Andean cloud forests. In some studies they were shown to be more effective in mixed-mating tree crops than even honeybees. More research will most likely show more value in this area.
Regarding pest control, we know there are many species of birds, especially warblers that primarily eat insects. But so do all of our North American woodpeckers. Many, if not most of these insects can have a detrimental impact on the trees or other plants where they’re found. One striking example is that of the spruce budworm. In the state of Washington, it is calculated that the value of birds eating these pests was calculated to be at least $1,473 per square kilometer per year. It also means that we are putting less toxic chemicals into the environment to control the ‘bad bugs’.
Even birds that we consider to be ugly provide a very valuable service. Vultures around the world are nature’s ‘clean up crew’. We may occasionally see vultures along the side of the road feeding on road killed animals, but they are also cleaning up after free range livestock that die away from the ranch and are not disposed of professionally. In India vultures were inadvertently killed when they fed on the carcasses of livestock that had been given a particular drug that led to kidney failure in the birds. In a chain reaction, with the decreasing number of vultures, feral dog and rat numbers went up, which led to an increase in rabies. An Indian economist calculated that from 1992 until 2006 this lack of vultures not only added to more human deaths from rabies, but also cost the
Indian economy $34 billion.
Those are all pretty staggering numbers and answers to the question posed by the title of this column. But there is one more value that is of particular significance to you, since birdwatching and birdfeeding is something you obviously like to do. Can you put a price on that pleasure? It is one of those things that a particular credit card company likes to call ‘Priceless’. It is also a hobby or pastime that generates millions of dollars in the U.S. economy.
By Kate Crowley