Protection needed for Global Travellers
Faraaz Abdool is looking out for high-flying tourists. He tells us how climate change and human expansion now threaten the amazing life and travels of shorebirds, many of which may be seen on the beaches and coasts of Tobago at this time of year.
White-rumped Sandpiper: Young birds on their first migration are inquisitive, like this White-rumped Sandpiper. Their curiosity disappears as they mature, perhaps an indication of learned behaviour. Photo by Faraaz Abdool
Discerning eyes may have noticed an influx of different looking birds within the past few weeks. Mostly various combinations of brown, grey and white, these supposed interlopers are shorebirds. They are not trespassing on our islands however; they are travelers and know no boundaries of country or territory. Breeding in the northernmost reaches of barely habitable land, shorebirds perform one of the largest mass migrations on the planet each year.
For us sedentary observers it will take some mind-bending to begin to understand the life of a nomad. Without the luxury and security of trains or aircraft, the only semblance of a protective exterior – for a time – is the bird’s own eggshell. Once it hatches as a tiny ball of downy feathers, it is surprisingly independent. Able to walk around after a few minutes, each hatchling is soon foraging for itself within their breeding grounds in the Arctic tundra. Time spent waiting in the nest to be fed is precious time wasted. In fact, their parents depart southward shortly after the eggs hatch!
This may seem cruel but it is by design, the adults leave the juveniles with unlimited access to all food sources to allow them to fatten up and gather the maximum amount of nutrition available for their maiden migration.
The young birds develop quickly, and grow their first set of flight feathers within a few weeks. Somehow, they all understand the urgency of the life they have inherited. Reluctance does not exist, for the cruel Arctic winter can arrive overnight and grind even the most determined of heartbeats to a halt. Wide-eyed and innocent, the young birds frantically feed almost continuously before gathering together, whirling in rapidly growing flocks over the tundra – testing their finely tuned flight mechanisms.
Shorebirds are extremely picky when it comes to habitat. They can only feed in areas that must not be too wet or too dry, not too hard or too soft. This means that migrating shorebirds cannot simply stop anywhere. Following their parents’ southbound path, the juvenile birds must fly non-stop for thousands of kilometres before arriving at a pre-determined stop-over site. These stop-over sites, sometimes referred to as “staging areas” are crucial to the survival of this family. Far away from where they hatched, the young shorebirds know to maintain their course to a sort of “promised land” where they replenish their spent resources.
Least Sandpiper: The Least Sandpiper is the smallest shorebird in the world with a maximum length of 15 cm. Photo by Faraaz Abdool
Some of these birds are absolutely tiny, weighing in at around 30 grams when fully stuffed just before departure. After a non-stop journey of 40-60 hours, some birds arrive at the first stop-over site having lost almost half of their bodyweight. They would then have to fatten themselves again, repeating the process a few more times until they arrive at their preferred wintering grounds.
At a latitude of just over 10 degrees north, our islands Tobago and Trinidad are both stop-over sites as well as wintering grounds for a wide variety of shorebirds: 33 species have been recorded on both islands over the years. Some species like the Semipalmated Sandpiper spend the entirety of the boreal winter here, while others such as the White-rumped Sandpiper would stay only a few weeks, fattening up for another leg of the journey to its ultimate winter destination in southern South America.
Shorebirds live on the fringes of what is considered physically possible. With such a fragile existence dependent upon a myriad of external factors, it is no surprise that this family of globetrotting birds is one of the most imperiled of all bird species.
Human activity is the root cause of all their troubles. Climate change affects them at every point as they continue to perform the unimaginable each year. Rising sea levels reduce the amount of tidal mudflats available for them to feed and roost along their migration route. Ambient temperature instability in the Arctic has altered snow cover which has in turn led to a crash in the population of lemmings – the primary source of prey for a variety of predators. Consequently shorebirds and their eggs have now become targets, resulting in diminished breeding success in recent years. Furthermore, warming temperatures in the far north are changing the nature of the landscape itself making it more and more unsuitable for nesting shorebirds.
Climate change is also upsetting the natural rhythm which was self-sustaining for millennia. A shorter spring season means that the window for shorebirds to arrive in their breeding grounds, find a mate, lay and incubate eggs has gotten even shorter. The explosion of insects on the tundra which is a primary food source for the young shorebirds is now happening sooner, often before many of the birds hatch. Without a reliable food source, the fate of their first migration may be doomed before it even begins.
Further south, the state of each stop-over site remains crucial to their survival. Throughout the world, rivers are redirected, deltas are filled in and mangroves are destroyed all in the name of development. Mudflats are often viewed as barren wastelands by humans. These are all critical refueling stations that can potentially make or break an entire family of birds.
Climate change – the result of human “progress” – cannot be overthrown by a single country. But this does not mean that we should throw our hands in the air. We need to make every effort to reduce our footprint, reforest areas especially mangroves, and most importantly halt the destruction of the natural world.
It may seem insurmountable, but we can all pitch in to provide some positive change that will benefit not only shorebirds, but all life on earth. Natural spaces need to be kept wild – if one is ever doubtful as to where deserves preservation the shorebirds will identify the areas for us. Wherever they are seen this September, they will return next September and the year after that. It is our responsibility - after their astonishing journey to our islands – to see that they have access to a clean, fertile and secure habitat – so that they continue to return, year after year.
Stray cat effect: Outdoor cats kill billions of birds each year. This stray cat caught and killed a Semipalmated Sandpiper that had just flown to Trinidad from North America - likely a non-stop journey. Photo by Shawn Baldeosingh.
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