The ecology of the Bahamian
(Abaco) pine forest
The ecology of
the Bahamian (Abaco) pine forest
A series of articles about the ecology of the Bahamian (Abaco) pine forest. In the last article we talked about the early stages of coppice type vegetation and the effects of animals (crabs) on the coppice ecology. If we continue moving easterly and overland away from the marls, we enter the pine forest. Our first concern quite naturally is to keep a sharp lookout for poisonwood which always seems to lurk closely by. We must watch our step due to the crevices and potholes (and a nasty twisted ankle). Finding a solid point we look up and see the two separate tree layers of the forest. The higher pine tree storey allows lots of light to come through while the secondary canopy or understorey is made up of softwood and hardwood shrubs and trees (coppice). This layer allows less light to penetrate.
We may be lucky and glimpse the hairy woodpecker moving behind a pine trunk to avoid our gaze. If not, we almost certainly will hear and see the noisy West Indian woodpecker with its bright red crown and tummy. Snaking up into the pine storey, the vines of the Virginia creeper curl and twist around the trunks covering them with a thick mass of foliage on their journey towards the heavens. If we are out here early enough in the morning, the mists and fogs swirling around the tree trunks will allow us spellbound glimpses of chic charneys and yaehoos who inhabit these areas. Among these brushes with the magical would be the sight of our native coontie emerging from the forest floor, pushing a rosette of palm like fronds upwards and spreading over, revealing a spectacular bright red fruit containing maybe a hundred bright fleshy seeds. The coontie or bay rush grows out of a think bulbous underground stem (similar to a sweet potato) full of starch.
Many hundreds of years ago the Lucayans and Arawaks harvested this tuber (they called it yuquilla) as a source of starch for food. However, before eating, the tuber was roughly grated into water and allowed to soak so as to remove the deadly poisons contained in the flesh. Cooking further destroyed these toxins. Today, of course, the coontie is used more as an ornamental along with other members of the cycad family known as the sago palms.
Even more interesting is the associated butterfly, the Atala Hairstreak. This butterfly lays its eggs exclusively on the coontie, the caterpillars feeding, making cocoons and emerging as adults all on this one plant. The relationship is good for both because the butterfly also pollinates the coontie "flowers." The hairstreak is notable for many reasons a few of which follow. The adult is perhaps an inch or so long, almost black with bright metallic blue glimpses along it, but with a most striking orange part on the body which is a warning to would-be predators (perhaps because of its poisonous diet). This is the same butterfly which always seems to be purposely crossing the highway in the pine yard just as the car you are in swoops down and swallows it through the radiator grill. But alas we are not here to dream of fairy tales and myths and days gone by which still live on for those who have seen them.
The pine forest lower storey also has its magical qualities for the flowers of the wild guava, five finger, palmettos and the pigeon berry with its bright blue flowers and golden fruit all add to the beauty that exists in this hot and unshaded place. We may also see the purple flower of the pine orchid growing out of seeming rock.
The land beneath our feet is very harsh being made up of thick crusty limestone pock-marked with potholes and hollows to trap one's feet. Yet out of this rockland the pine and broadleaf bush grow and thrives, often so thickly it is impossible to push our way through. This is the pine land, host to so many bird species, including the Abaco parrot, the elusive Kirtland's warbler, the Cuban grassquit, woodpeckers, rad tailed hawks, owls and, of course, the vulture or buzzard. Each one has its own specific function here in the ecology of the woodland. Here also we find the curly tailed lizard, the anoles and the boas, all contributing to the balance of life from their burrows and holes amongst the greenery.
At night the atmosphere comes alive with the blinking lights of the fireflies and the lightning bugs, signalling each other with the non-ending ritual of flickering sexuality and reproduction. During the day we will be pestered by the doctor fly and the yellow Hanna, both of which can draw a good welt and a sizeable pool of blood.
Here is the pine forest where the days are hot and the nights very cool, being on average some 10 degrees colder than the coppice land and the coastal settlements of the island. Here in the pine forest where the introduction of exotics (not native) such as the wild domestic cat, the hog, man and now the raccoon will all have their own specific effect on its ecology.
The pine forest was considered by past generations to be essentially worthless and so named the pine barrens. It is only in the last 100 years with the coming of large scale lumbering and now with the use of mechanised agricultural land equipment that the economic value of the pine yard has been realised. All of these and other physical aspects of nature such as fire and hurricanes will have their own effect on the ecological succession in the pine community.
In the Northern Bahamas the pine forest is the apparent dominant ecotype and to some becomes boring with mile after mile of endless drives with no other view than a solid wall of fire blackened Bahamian pine tree trunks. It may seem odd that only Abaco, Grand Bahama, Andros and New Providence support pine stands in the Bahamas while the Southern Bahamas produce none.
The pine barrens is one of our most sensitive ecological systems and we as people can and do affect natural controls such as the fire factor and exotic species changing the existing ecological balance. Consider the expected vulnerability of the parrot to wild cats and now the raccoons so recently introduced to Abaco. But what about the effects of our native species such as crabs and snakes on this same population? Will these new exotics simply add to the destruction of the parrot squabs (chick) or displace the native predators already there? What about the increase of fire intensities in recent years. Will this affect the foraging habits of the parrots during chick rearing (fire season) by food source destruction and will the rearing success rate decline? The answer, of course, lies in our own minds because we as humans are the ones who eventually place the value and level of importance on our surroundings and so the ability for wilderness areas to survive. But that is another topic for another times.