"Nowadays people know the price of everything and the value of nothing."  ~Oscar Wilde

Survival of the fittest or all animals are equal, but some animals are more equal than others

Multiple factors are threatening the survival of the West Indian herpetofauna and currently the situation looks grim. While one might argue that the general situation on our planet is nothing short of catastrophic, we would like to focus here on the ecosystem threats and other factors affecting the West Indian herpetofauna. We hope that our words inspire our readers to think further and take action. It seems humankind has opened Pandora’s box and, as in the mythology, the seven bringers of evil are out in our world: envy, remorse, avarice, poverty, scorn, ignorance and inconstancy. However, as in the the ancient Greek mythology, there is Hope which still persists. We consider all conservation efforts, including ex-situ conservation, as the glimpse of Hope that is dearly needed to keep everyones’ efforts moving in the right direction.  While Hope is not a method, it is  sometimes the only motivation that keeps us going.

We aim to provide the most complete account of threats, since we were surprised to notice that even in the current scientific literature regarding the West Indies e.g. , several important points, such as climate change, housing projects, pollution, agrochemistry and others are not fully adressed.

The West Indies is generally a region well investigated by scientists, despite the more than 7000 islands, cays, islets and banks.  It is difficult to provide a general analysis of threats and conservation of West Indian boas, owing to the fact that the West Indies are comprised of a diverse set of Islands of various sizes, climates, geological origin while geopolitically belonging to 13 independent states and 19 territories belonging to other countries.  We therefore aim to give a generalized overview but are aware that this is incomplete and reflects, at best, our knowledge at the time of writing.

The insular West Indian area is one of the world’s biodiversity hot spots because of their high species-richness, endemism and level of threat .  The UN Millennium Development Goals for 2020 through its Aichi Biodiversity Target 11 seeks to protect 17% of terrestrial areas and 10 percent of nationally administered marine areas (http://www.cbd.int/sp/targets/).  The West Indian protected areas, established to safeguard biodiversity in the region, occupy approximately 11–15% (25,804 km² – 36,000 km²) of the land surface .

Insular biogeography: more than a theory

Immigration and extinction are mutually inclusive.  That is to say, they determine the number of species found in an isolated ecosystem such as those found on islands.  The number of species found on an island is determined by how large the island is and how far the island is from the mainland.  The larger the island, the likelihood of species extinction is much lower or the rate of extinction is slowed.  This is referred to as the species-area relationship.  This relationship can be both observed and mathematically predicted.  Using this same theory, the smaller the island, the fewer species are typically found.  This is referred to as the species-distance relationship.  Alfred Wallace, a British naturalist and explorer,  developed this theory in the mid 19^th century to build upon Darwin’s theory of evolution.

The size of an island and its distance from the mainland interact with immigration (colonization, the orange lines) and extinction events (green lines) to influence the number of species. This is known as the Wallace Line. (https://biologydictionary.net/island-biogeography/)  This relationship can be best explained using the chart below.

The need for Conservation

Not a single West Indian species listed as threatened on the IUCN Red List has been re-classified to a reduced threat status; instead, a large number of species have been either elevated to a higher threat category or have been added to the threatened list with each subsequent revision .  The West Indies has had a disproportionate number of extinctions and extirpations and currently possesses a worrying litany of threatened species.  Following the latest update on 10 December, 2020 there are now 128,918 species on the IUCN Red List, of which 35,765 are threatened with extinction.

As of 2012, 2052 species have been placed on the ESL (Endangered Species List) as endangered or threatened.  Billions of dollars have been spent on species listed by the ESA (Endangered Species Act).  In the 40 years since their placement on this list, just 28 species have been removed from the list.  And 10 of those 28 species were removed due to extinctions; effectively only 18 species have come off the list in those 40 years.  All the species remaining on the list are in the same, or greater, danger of becoming extinct.  This entire program has a success rate of just one percent .  Twelve percent of ES (Endangered Species) on the U.S. ESL receive their prescribed funding as listed in the recovery plans.  Approximately fifty percent of ESA-listed species continue to decline or remain at high risk for extinction .

The last 500 years have resulted in major extirpations and extinctions across the West Indies, beginning with the Taino Indians’ use of large edible terrestrial species such as the  Iguana (Cyclura).  Beginning with the arrival of the Europeans came a massive wave of extirpation and extinction through large scale deforestation for sustainment agriculture and human settlement .  The colonists also brought rats, mice, the mongoose, cats, dogs, cattle, goats and pigs to further the list of extirpations and extinctions.

Extinction Dynamics

Species that appear especially vulnerable to extirpations and extinctions are boids (Chilabothrus) and diurnal, ground-dwelling colubrids (Alsophis spp. and Liophis spp.). Alterations in the prey base and habitat destruction are likely responsible for declines in Chilabothrus populations, whereas predation by mongooses, cats, and rats have taken their toll on species of Alsophis and Liophis .

Our presence on this planet has caused herpetofauna to speed up evolutionary changes through deforestation and habitat destruction; this change now takes place over a few hundred years instead of tens of thousands of years.  It can be measured in less than a few hundred generations.  Over harvesting, habitat fragmentation, exotic species and chains of extinction are considered the most important factors that cause contemporary extinction-these are known as the Evil Quartet .

By far the single most important threat to life on the islands is habitat destruction and alteration.  Habitat loss effects the weather, flora, fauna and prey base.  It also prevents the re-introduction of species due to lack of suitable habitat.  Nowhere is this more evident than in the West Indies.  While some species appear capable of adapting to modified habitat with apparent success, this results is the species being touched by the winds of the vortex of extinction.  Those species that live in habitat fragmentation are especially vulnerable to extinction as a result of various factors that include Minimum Viable Poplulation (MVP), Allee affect, backgound extinctions, trophic cascading, extinction debt, etc., .

Conservation efforts

Conservation efforts differ largely between the different governing entities of the islands and the actual implementation of those efforts.  For instance, the Bahamas have very strict laws against wildlife exploitation or export, however at the same time allow construction and habitat destruction to occur without regard for the flora and fauna.  This can be said of most of the islands in the region; tourism is a valuable source of income for the island governments.  The sticky wicket is finding the proper balance between the income generation by tourism and agriculture and the conservation of island wildlife.  When an island government sells a marine sanctuary, a preserve or conservation area, one can’t help but wonder where the leadership loyalties and priorities lie.

Any attempt at conservation must include a “what’s in it for us/me” at the macro and micro Island level.

Endangered species (ES) by the book

ES are regionally managed by different types of plans that all have one goal in common.  That is, how to best manage the genetic diversity of the ES in their charge.  These plans and road maps are regionally different by name and institution.  We have listed below those institutions and their tools used in pursuit of these conservation goals.

• Americas: Species Survival Plan (SSP).  Association of Zoos and Aquariums (AZA), Canadian Association of Zoos and Aquariums (CAZA).
• Europe: European Endangered Species Programme (EEP).  European Association of Zoos and Aquaria (EAZA).
• Australasia: Australasian Species Management Program (ASMP).  Zoo and Aquarium Association (ZAA).
• Africa: African Preservation Program (APP).  African Association of Zoological Gardens and Aquaria (PAAZAB).
• Japan: Conservation activities of Japanese Association of Zoos and Aquariums (JAZA).
• South Asia: Conservation activities of South Asian Zoo Association for Regional Cooperation (SAZARC).
• South East Asia: Conservation activities of South East Asian Zoos Association (SEAZA).

Regional Threats

We categorize the threats on the islands in order to provide a detailed overview.  Note that some threats are of a global nature, while others affect West Indian Boas on a regional level.  We discuss the following in subsequent chapters.

1. Biological invasions
2. Changing of natural land into farmland
3. Changing of natural land into housing projects
4. Changing of natural land into other projects (e.g. ports, waste disposal, industry )
5. Chemical uses (herbicides, pesticides)
6. Climate change
7. Deforestation
8. Growth of the human population
9. Increase in tourism
10. Pollution (air, water, land)
11. Wildlife exploitation
12. Weather (wind & storm damage)
13. Drug trade & crime

In a recent study, Leclerc Courchamp and Bellard analysed the risks for species extinction on island ecosystems worldwide.  They analysed 15 insular regions, applying novel network analysis methods which enabled them to disentangle the associations of multiple threats on vertebrates, invertebrates, and plants.  They came to conclude that biological invasions, wildlife exploitation and cultivation, either alone or in association, are the three most important drivers of species extinction and decline on islands .  

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