by Larry Smith
Five centuries ago, the Amerindian inhabitants of the Bahamas lived in a completely different world from the one we know today.
Early European explorers described flocks of parrots “darkening the sky”, dense hardwood forests, and sea turtles so numerous they kept sailors awake by constantly knocking against ship hulls.
Seals and iguanas crowded the shorelines; whales were a common sight offshore; and lobster, conch and fish were abundant. Evidence for this are the large mounds of discarded conch and other shells and fish bones that are a ubiquitous feature of Lucayan archaeological sites.
And since slow-moving conch once abounded in shallow water, they became a staple food for the European settlers - giving rise to their nickname, “conchs”, which persists to this day in the Florida Keys. In the Bahamas, the sobriquet has mutated into “conchy joe” - meaning a white or mixed-race Bahamian.
When South Florida was an impenetrable wilderness, Bahamian ‘conchs’ looked upon the Florida Keys as northern out islands. In fact, Key West is famously known today as the conch republic, and early American dictionaries define conchs as “illiterate settlers of the Florida Keys" - meaning Bahamians, both black and white.
But today, the delectable queen conch – the one we all love to eat – is in serious trouble throughout the region. And that Bahamian delicacy, conch salad, is in danger of becoming a thing of the past. Florida’s conch fishery collapsed decades ago, and conch harvesting was banned throughout the continental United States in 1986.
So most of the 1,000-plus metric tons of conch consumed by Americans each year is imported from a handful of countries like the Turks & Caicos, Belize and the Bahamas, where conch populations have been in somewhat better shape.
But new research shows that the Bahamian conch fishery is also in danger of collapse.
A key point to consider is that conchs don't reproduce when their numbers fall below a certain density. That’s because – like groupers - they gather in large spawning aggregations to breed. Within a few days, the eggs hatch into larvae that can float more than 100 miles from their point of origin. And after a few weeks the larvae settle on the seafloor to become juvenile conch – miniature versions of the adult mollusks we are all familiar with.
These juveniles bury themselves on the sea bottom to escape predators, spending more time on the surface as they grow, eating algae and detritus in the sand. They take several years to mature and can live as long as 20 years. But as we all know, they are ill-prepared to deal with human fishing pressure.
Scientists used to say that, throughout the region, only the offshore Pedro Bank in Jamaica and the Exuma Cays Land and Sea Park have average densities of conch greater than the threshold needed for reproduction (about 50 adults per hectare).
But researchers now say that even in the Exuma park (which has been a no-take zone since 1986), conch densities have dropped 35 per cent over the last 17 years, suggesting that the population is no longer self-sustaining.
New research has been conducted by Martha Davis, Catherine Booker and Dr Allan Stoner, a top scientist with the US National Marine Fisheries Service who led a multidisciplinary group studying conch ecology and conservation in the Exumas during the late 1980s. Davis and Booker are both environmental scientists who have spent a lot of time in the Bahamas and are collaborating with Stoner.
It was Davis who founded the non-profit research group called Community Conch, which has conducted three surveys in the Bahamas since 2009, with support from the government and local conservation groups. The mission of Community Conch is to support sustainable conch populations in the Bahamas through research, education and collaboration with local communities.
"So far, every place we’ve studied in the Bahamas - Andros, the Berry Islands, and the Exuma Cays - we’ve seen evidence that conch stocks are declining, and in some cases severely declining," Booker told me. "The Bahamas is now experiencing what other countries in the Caribbean have been struggling with for decades."
Community Conch has prepared a technical brief on its research, and the Department of Marine Resources is considering new policies to better manage the Bahamian conch fishery. The research brief is based on data collected 17 and 20 years ago by Dr Stoner, matched with comparative data collected in the last three years by Community Conch under Dr Stoner's direction.
Researchers observed no mating at all with a density of less than 47 adult conch per hectare in the protected waters of the Exuma park, or at two traditional fishing grounds in the Berry Islands and off Andros. Logistic modeling suggests a 90 per cent probability of mating occurring at 100 adults per hectare in the un-fished area, but mating frequencies increased more slowly with density on the fishing grounds.
"Mating frequencies were 6.3 per cent in the Berry Islands and just 2.3 per cent at Andros," the researchers said. "In contrast to the marine reserve, 90 per cent probability of mating required 350 to 570 adults per hectare at Andros and the Berry Islands respectively."
So having conch in the future is based on our ability to maintain sufficient population densities in the present. And this is further complicated by the fact that the animals are slow to mature, meaning they are often harvested before they have a chance to reproduce.
According to Catherine Booker, Community Conch recently studied the relationship between the age of a conch and its stage of reproductive maturity. "What we found, and what other scientists have found throughout the Caribbean, is that the queen conch needs to be older than we thought before it is capable of reproducing.
"We estimate age by looking at the thickness of the flared lip of the conch shell, and it turns out the lip actually needs to be about 15mm thick before a conch is sexually mature. Based on our work and others', female conch are probably not mature until they are at least five or six years old. Males mature a bit younger."
But the most important factor affecting conch stocks is fishing pressure. Improved diving gear, the use of freezer storage, and habitat degradation from development all add to the dramatic decline of the fishery throughout the region. This means that getting reliable data is key, so that marine resource managers can know what they are dealing with.
In the Berry Islands, for example, Community Conch found that juvenile populations in important nursery grounds that were studied in the 1980s had declined a thousand times to only a few hundred individuals by 2009. And of the eight historical fishing grounds surveyed off Andros in 2010, only one had adult densities allowing minimal reproduction.
Last year, Community Conch surveyed sites in the Exuma Cays that had been previously studied by Dr Stoner and others. They found that the overall density of adult conch had declined substantially over the last two decades, and the population had aged significantly.
"These results are expected when the adult population is not being exploited but where recruitment has slowed," Community Conch said. "We conclude that the park is not large enough to hold a self-sustaining population…A single marine reserve such as the ECLSP cannot protect a species with pelagic larvae when the population outside the reserve is heavily exploited. Rather, a network of marine reserves is needed to provide a chain of reproductive sources."
From this research the scientists conclude that conch densities in commercially fished areas of the Bahamas are decreasing to levels that will not sustain the population. Fishing grounds in the Berry Islands, Andros and Lee Stocking Island in the Exumas all show evidence of collapsing populations.
And although the Exuma park protects existing conch, there is not sufficient recruitment from outside the protected area to maintain conch populations within the park, and further decline is expected if there is no change in fishery management policies.
"Queen conch populations are rapidly declining below critical thresholds for reproduction and they are being harvested before sexual maturity," Community Conch said. "Experience in Florida and other Caribbean nations show that recovery of conch populations is very slow after populations fall below those thresholds. Releases of hatchery-reared conch have not been successful in rebuilding stock, and natural populations need to be conserved."
According to Booker, "the reality is that it is much easier to make management changes now before it is too late. The current regulation of requiring a flared lip combined with minimal enforcement has produced the current situation. We like to say, if you can break the lip, that’s an immature conch, so don’t take it. The need to set priorities and implement a conch recovery plan is critical and urgent"
New management policies recommended by the scientists include an expansion of marine reserves to include appropriate conch habitat; banning the use of hookahs to harvest conch; establishing a lip thickness criterion of 15 mm; setting quotas for conch landings; and implementing a closed season on conch between July and September.
One key recommendation is to end conch exports. The United States now is the largest consumer of imported conch, buying more than 80 per cent of the conch available for international trade. And conch has been legally exported from the Bahamas since 1992 - almost 600,000 pounds last year alone. This only increases the fishing pressure on conch stocks.
"Closing off legal exports would reduce the pressure on local conch populations," Department of Marine Resources Director Michael Braynen told me recently. "Conch exports are still allowed because fishermen say they 'need' the income, after the local demand for conch has been met."
But it makes little sense to allow the export hundreds of thousands of pounds of conch meat every year, while watching the decline of this key Bahamian fishery. Over the years conch fisheries have been closed in Cuba, Florida, Bermuda, the Dutch Antilles, Colombia, Mexico, the Virgin Islands and Venezuela.
Do we really want to see the end of this cultural catch in the Bahamas? Support conch salad for Bahamians first - and end conch exports!