The story of the Queen conch (Aliger gigas) in the last hundred years is one of epic proportions. The plot unravels on the high seas in some of the most beautiful and biodiverse Caribbean landscapes. There are heroes and crusaders, small desert islands, and pirates. The stakes are life, death, and extinction. The protagonist is a large sea snail that lives in benthic zones throughout the Caribbean. As it develops through juvenile and adult life stages, it builds a distinctive spiral shell and flared lip—a shell that, according to a popular folk myth, if you lifted one to your ear, you might hear waves crashing inside.
Despite its beautiful exterior, Queen conch is most valued for the meat within its shell. The Queen conch fishery is an important part of the Caribbean region’s economy, culture, and marine ecosystems. This sympathetic character is facing decline, and has been since the 1960s, due to diverse impacts including habitat degradation, pollution, and overfishing. These effects occur at many scales and affect juvenile conch survival to maturity and population replenishment.
Belize is a small Central American country that is home to the Belize Barrier Reef, the second largest barrier reef in the world. The Belize Barrier Reef ecosystem is home to a wide range of species, including the Queen conch. In Belize, both national and international efforts have worked to combat conch population declines through fishery regulations and habitat conservation. Yet as in many stories, forces that appear to be all good or all bad actually fall somewhere in the middle. Existing conservation efforts sometimes ignore the cultural and economic importance of conch as a source of income and food for many people. Marine reserves and fishing regulations cannot completely curb poaching that occurs in protected areas.
Years of field research to study juvenile populations of Queen conch in Belizean marine reserves have allowed us to document the many facets of its fishery and ecology and record one small part of the Queen conch’s story. This series of photos describes Queen conch life history, the Belizean Queen conch fishery, and conch conservation efforts. It shows threats to conch as well as the challenges we must overcome to effectively manage and conserve this species.
In the beginning, Queen conch hatch from eggs as pelagic, microscopic larvae. After hatching from an egg, they drift near the top of the water column, feeding on phytoplankton, growing, and developing. Once they reach the end of their larval stage, trophic cues from macroalgae and the sediment in seagrass habitat induce them to morph into a benthic post-larval stage. During this stage, they settle onto the ocean floor in or near seagrass habitat. They live buried in sediment for about a year, eating tidally circulated macroalgae.
After emerging from the seafloor sediment, they continue their bildungsroman by forming large juvenile aggregations within seagrass beds in shallow, clear waters, where they continue to grow and begin building their shells. Juvenile conch attain sexual maturity around three to four years of age, when their shell ceases to grow in length and instead begins to thicken the shell’s flared lip. This lip thickness can be used as a natural index of measure for sexual maturity and adulthood.
Once completely mature, adult Queen conch have a big, showy shell. The shells are characterized by their large size and spiraled shape, the pointy spires that encircle the top, and the bright pink to orange color of the shell interior. The snail’s body is protected by a hard outer operculum that covers the shell opening and is used to propel it around on the seafloor. Adult conch inhabit a home range area that includes foraging areas. They do not limit themselves to seagrass habitat, and may inhabit hardbottom areas of patch reef, sand, or coral rubble. Because conch live in groups, take many years to mature, and have a limited range of motion, conch reproduction (pictured in Figure 5) is timing- and density- dependent. There must be enough adult conch living within a certain area to successfully reproduce and maintain a viable population.
Overfishing and poaching within the Queen conch fishery may appear to be the “villains” in this story, and they are the main causes for the decline in conch populations in Belize. The conch fishery is focused on shallow areas where large aggregations of juvenile conch are easily accessible from a boat without much expensive fishing gear, extra time, or effort. Fishing pressure is thus highest during the juvenile stage of a conch’s life, removing individuals from populations before they have an opportunity to reproduce.
However, the conch fishery in Belize is rooted in traditional and cultural roots. Conch is an important element of traditional Caribbean cuisine, where they are eaten raw and cooked in soups, fritters, and salads, typically for home consumption and subsistence. In the last century, though, commercial harvest of conch has become increasingly common, and these combined harvests have caused conch populations to dramatically decrease. In 1972, conch harvests peaked at more than 1.2 million pounds, and in 2022, 951,000 pounds were harvested for export alone (Statistical Institute of Belize 2022).
The relative ease of conch fishing and processing may also facilitate extensive harvesting. After picking a conch out of its benthic habitat, harvesting the meat involves simple tools—a hammer and knife, or other similar objects. The hammer is used to knock a small hole near the top of the conch’s shell at the single place where the snail’s body is attached to the shell. Next, the knife can be pushed through the hole to push the meat out through the main opening in the conch’s shell. An empty conch shell with a hole in its spire indicates that the conch meat has been harvested by humans.
The evidence left behind by heavy commercial fishing is easily seen in Belizean waters. Conch harvest for the meat removes the snail from its shell, leaving the shells behind. Because the shells are heavy and take up large amounts of space in small fishing boats, they are often discarded back into the waters where the conch were found or left in piles on and around the small cayes that dot fishing grounds, creating stark “graveyards”, or middens, of empty conch shells. These piles are a powerful way to visually quantify conch harvest.
National and international efforts to save the conch, or at least combat overfishing, have relied on restricting conch harvest in time and space. Several national fishery regulations have been imposed in Belize. A conch fishing season has been imposed and lasts from October to June, and fishing with SCUBA gear is not allowed. Take limits attempt to shift fishing pressure away from juvenile populations by requiring that harvested conch be of a certain size, to help avoid harvesting conch that have not yet reached reproductive maturity. The shell of a conch to be legally harvested must be at least seven inches long, and a meat fillet to be sold must weigh at least three ounces.
To supplement fishery regulations, a system of marine reserves has been established in Belize to protect the Belize Barrier Reef from development and maintain populations of commercial, recreational, and endangered species—including Queen conch. Research has described both benefits and shortcomings of this strategy, but marine reserves represent a step towards protecting valuable fisheries and the habitats on which they depend. Twelve percent of Belizean waters are protected in seven marine reserves. The areas outline zones where different levels commercial and recreational activities are allowed. This map shows marine protected areas (MPAs) in Belize as of June 2024 (MPA boundaries UNEP-WCMC and IUCN [2024]).
Any Queen conch that are harvested under the size limit, with SCUBA gear, out of season, or within a protected area are illegally poached. This often occurs throughout Belize, even within marine protected areas. In a small country with a history of subsistence fishing and a limited job market, conch “pirates” can make a living from the conch fishery outside of set management regulations. Simple, small boats with one outboard motor are often used for conch fishing, as they are easily operated by one person and can easily navigate in shallow areas where juvenile conch aggregate. Many commercial and subsistence fishers travel to the Belize Barrier Reef from the Belizean mainland to fish for extended periods of time, and stay in small fishing shelters on various cayes. Unfortunately, queen conch life history traits make them easy targets for fishing, as they are slow moving, easily visible, and live in large groups in shallow areas that are simple and quick to access without excessive expensive fishing gear.
The unique setting and influential forces in the story of Queen conch make for dramatic ongoing action that hurtles toward a climax, though the outcome of its resolution is yet to be determined. Since Queen conch physically record impacts to their populations through their shells, tracking shells can provide information about population and survival. Years of field research on juvenile Queen conch aggregations allow us to record and interpret the information they share.
Queen conch populations can be surveyed in several ways. One focuses on measuring juvenile aggregations in shallow water through transect surveys, which can be done while snorkeling. Within a randomly selected location of conch habitat, a transect rope can be rolled out underwater, and any conch or conch shells within a certain area of the line can be picked up and measured. Data on conch length, lip thickness, survival, and whether or not the conch shell shows the typical hole in the spire after harvest. Developing a record of this information that describes juvenile conch aggregations Queen conch populations within a certain area will help measure trends in survival and poaching pressure within protected areas over time. This knowledge will help us quantify fishing pressure, survival, and the life stages of conch that inhabit shallow water in different areas over time.
The epic tale of Queen conch survival, study, and conservation is a long, complex, and unresolved one. The unique life history and physical characteristics of Queen conch make them a beautiful, meaningful part of the Caribbean economy, gastronomy, and cultural heritage, but also make them especially vulnerable to threats from overfishing, pollution, and habitat loss. To combat this, conservation strategies impose management restrictions on the conch fishery and establish protected areas, but the efficacy of these approaches is yet to be determined. Continued research on juvenile Queen conch aggregations can help track population characteristics, survival, and fishing pressure. Knowledge gained from this story will hopefully allow us to make management decisions to help conch flourish in the future, giving the Queen conch’s story in Belize a happy ending.
We would like to thank the Belizean fishers and guides who shared their stories, livelihoods, and traditional ecological knowledge with us. Their insight continues to help direct our research efforts. Thanks are also due to the University of Alabama Geography Department for their support.