The Lesser Antilles: a Lesson in Conservingnatural Resources

The Lesser Antilles: A Lesson in ConservingNatural Resources

Raymond W. Doyscher, Jr.

is the name given to an arc- THE LESSERANTILLES TABLE1. Summaryof Krakatoa'sHistory of Re-biogenation* shaped chain of numerous small islands in the Carib- Downloaded from http://online.ucpress.edu/abt/article-pdf/41/2/86/36865/4446484.pdf by guest on 26 September 2021 from Puerto Rico southward to the bean, stretching Year Biotic CommunityObserved northern coast of South America. Geological records indicate that the oldest islands in the chain began to 1881 Volcano-no recordedlife form exist. emerge from oceanic volcanoes 30 millionyears ago. 1884 1 spider. No other life forms recorded. Martinique, Dominica, and Guadeloupe were com- floweringplants. pletelyformed 25 millionyears ago, St. Vincentabout 10 1886 11 ferns, 15 millionyears ago. 1897 Much green covering. Coconut trees on the island the edge common. Sugar cane common. 4 orchid Latercoral reefs made theirway to ocean surface species. on the easternedge of this islandchain. They evolvedas 1907 263 animalspecies-including insects, birds,reptiles, a result of the incessant and tenacious activityof tiny and land-snails. marine animals working on the volcanicallyelevated 1930 Dense forest coveringthe whole island. Muchgrass- ocean floor. From this coral emerged EasternGuade- land with wildflowers.Almost 50 species of verte- loupe, Anguilla,Barbuda, and Antigua.None of these brates. Two mammals-bats and rats. 1,200animal islandshas ever been a part of a continentalland mass. species observed. They offer biologists a unique opportunityto observe and identifyprinciples of ecology and conservationthat exist nowhere else on earth. *Basedon informationfrom Moore 1964. Island The Physical Conditionsof the Physical differences occur in the topographical fea- The islandsare tropical.the hot equatorialsun domi- tures. These features directly affect the soil condition nates the climateof thisarea, and little seasonal variation and the quality of rainfall that, in turn, affect the biotic occurs. The directionand velocity of the wind and the community. Rainfall can, in fact, vary greatly from one tropicaltemperatures are, for the most part, shared by part of an island to another. Three hundred inches may all these Lesser Antillesislands. fall annually on Mt. Diablotin on the isle of Dominica, but the sea-level area may receive only 50 inches. Likewise, RaymondW. Doyscher, Jr., has been teachinga on St. Lucia, rainfallis over 150 inches in the mountains varietyof science courses for the past ten yearsat but less than 60 inches on the beach. In the more level, East Detroit High School, East Detroit,Michigan nonvolcanic island, Barbados, the island center gets 80 48021.He receivedhis B.S. degree in biologyfrom EasternMichigan University in 1965;his M.A.de- inches as compared to 50 inches on the shore. gree in educationalpsychology from Wayne State Universityin 1968;and his M.S. degree in biology The Originof the IslandBiology from the Universityof Montanain 1971.At East A Detroit High School, the courses Doyscher has 11, For insight into the biotic origins of these islands, I con- taught included biology, chemistry, physiology,conservation, and physicalanthropology, a course he designedhimself. Many of his les- sulted three sources: (1) the biogenesis advocates of long sons are basedon colorslides taken on his travelsthroughout the Uni- ago; (2) the information supplied by the lava-covered Isle ted States andabroad. This article is basedon slidestaken during a visit of Krakatoa; and (3) some experiments conducted by to the Lesser Antilleswhere he investigatedthe physicalorigin of the islands,their biological development, and the effectof humanoccupa- Charles Darwin. tion on the naturalhabitat of the islands.Doyscher's sources of infor- Redi in the 17th century, Spallanzani in the 18th cen- mation included island guides, natives, and experienced fellow tury, and Pasteur in the 19th century have virtuallyelimi- travelers,all of whom were eager to share their knowledgeof the Antilleswith him. Doyscheris an activemember of NABT,and he has nated any possibility that these islands were populated publishedpreviously in Science Review. by spontaneous generation. They successfully con-

86 THE AMERICAN BIOLOGY TEACHER, VOLUME 41, NO. 2, FEBRUARY 1979 * ... a T~3o 28OURHA PAS +

ATLNTI

rs~~~~~~~~~~~~~~~~~ /\c OCEAN~C/ X I r4 Downloaded from http://online.ucpress.edu/abt/article-pdf/41/2/86/36865/4446484.pdf by guest on 26 September 2021

JAJI1l PiJEgro J~~~~~~~~~~~~~cos Ar ?R

DOMRINICA $EA G00A PR84

l ~~~~~ANTILLESeO VIA/ET

C ACv T5 R0Rr.40

FIGURE1. Geographicallocation of the Lesser Antilles. vinced the scientificworld that life can come only from America, Central America, and the older Greater pre-existinglife (Asimov 1964). AntillesIslands. The second source of informationexamined in the Scientists know that once an islandemerges from the data collectedon the repopulationof an islandin the East depths of the oceans, the floraand faunasoon reappear Indies, which was wiped clean by a volcanic eruption. in both abundanceand variety.It is also accepted that The island, Krakatoa, was rendered a lifeless, lava- the bioticoccupation had to have livingancestry on the covered rock afteran eruptionin 1883.With a greatdeal mainland.Yet an importantquestion remains. How did of intrigue,biologists reported how the islandrecovered lifeget fromthe mainlandto the islands?Charles Darwin, its floraand fauna.Table 1 traces Krakatoa'sattempt to the third source, offers some insights on the originof repopulate. islandlife. Naturally,Krakatoa's biology is still changingand will In his book,The Originof Species (1960),Darwin de- continue to change. Even in an ecologicallyclimaxed scribedhow he investigatedthe "meansof dispesal,"the area, a disease or the introductionof new competition way an organismgets from one area to another. His can quicklyand dramaticallyalter the course of a seem- experimentsand observationsmay be summarizedas inglystable and quiet ecosystem. FromKrakatoa's story, follows: we can gain insightinto the privitivebiotic development Darwinclaimed he germinatedseeds thathad been left of each of the CaribbeanIslands. The originalimmigrant in salt water for as long as four and one-halfmonths. species would have come from South America,North Branches carryingseed-containing fruit were observed

LESSERANTILLES 87 to float for three months. Soil trapped behind a rock sur- rounded by a tree root sometimes contains viable seeds; Darwin dislodged three seeds from a 50-year-oldoak tree and found that they still had the potential for germinating. Darwin had very little difficultygerminating seeds from excrement and from pellets disgorged by birds. He force- fed seeds to a seed-eating fish, and then fed the fish to birds. After the contents passed through the digestive track of these fish-eating predators, the seeds were separated from the excrement. They, too, germinated. From the leg of a dead partridge, a six-ounce "ball of earth" yielded enough seeds to grow 82 plants. In another separately cited incident, Darwin told how a "lit- tle cake of dried earth" yielded a seed of a Juncus bufonius, which germinated and then flowered. Darwin also reported sighting a swarm of wind-blown FIGURE 2. Marigot Bay in St. Lucia-a large mountainous rain forest Downloaded from http://online.ucpress.edu/abt/article-pdf/41/2/86/36865/4446484.pdf by guest on 26 September 2021 island. locusts flying 370 miles off an African shore. The implication and revelance of these experiments are obvious. Nature is not without methods of populating Kitts, St. Lucia, St. Vincent, Tobago, and Trinidad are isolated islands. The islands' ancestral life would the oldest and largest of the island chains. Because of originate from four sources, including: their exaggerated mountain peaks resulting from vol- 1. Flying animals. Birds, insects, and bats would come canic activity, these islands receive copious amounts of lost in storms or would arrive while following migrational precipitation. Moisture-carrying clouds forced to rise as patterns. With unoccupied ecological niches existing, they pass the high peaks cool rapidly, and the resulting the invitation to remain would be too good to decline. condensation is the source of the rain forest's moisture 2. Floating debris. Branches with fruit, old roots, or supply. Some representative figures of annual rainfallin fruits alone, are able to transport an endless variety of the island's rain forests are: Dominica, 250 inches, St. embryonic forms, including seeds, insect eggs, and prob- Lucia, 150 inches; Grenada, 140 inches; and St. Vincent, ably reptile eggs. Logs dislodged from shores in which 100 inches (Macmillan 1974). live snakes are housed could also serve as carriers. In addition, the volcanic soils are rich in minerals. With 3. Seeds from gullets, feet, and plumage of birds. Most plentiful water, fertile ground, and an equatorial sun, the seeds are small and protected by a hard coat making flora and fauna would have existed in almost an endless them resistant to desiccation and digestion. Seeds de- variety. We can verify this through the present existence posited from a bird's alimentary canal even have the of virgin tropical rain forests in South America. Further- advantage of an immediately fertile environment. more visitors to the islands can still observe a secondary 4. Air drifts. Fern, algae, and fungal spores have a reforestation of what was once undisturbed wilderness. weight and density equivalent to that of dust particles. According to one record, Columbus described a rain Such migrational attributes highly increase the likeihood forest in Hispaniola as follows: of early arrival to islands. In fact, their early arrival is necessary for such specimens to achieve a primaryposi- ... Its lands are high and there are in it very many sierras and very loftymountains, with tion in ecological succession (Doyscher 1967). beyondcomparison the islandof Teneriffe.All are most beautiful,of a thousandshapes, and all are accessible and filledwith trees of a thousand kinds and tall,and they seem to touch the sky. And I am told that The Islands Prior to European Occupation they never lose theirfoliage, as I can understand,for I saw them as green and lovely as they are in Spain in May and It is interesting to speculate on what these islands some of them were flowering,some bearingfruit and some looked like to Columbus and the early European visitors in anotherstage, accordingto theirnature (Richards 1%4). to the Caribbean. Three types of islands would have been conspicuous to Columbus: the rain forest islands, When left undisturbed by civilization, tropical rain lush with vegetation, large and mountainous; the sea- forests appear dense from the outside. Actually, this is sonal forest islands, drier, smaller, and more level; and only a canopy effect. Had he left the shore and gone into the coral islands, very small, level, and dry. the mountains, Columbus would have found himself The only people who would have seen the Caribbean amidst a covering through which little light penetrates. rain forest islands in their virgin state would have been The old tree trunks would have been impressive, but the the native American Indians and the early European sai- absence of ground cover and forest litter would have lors. These islands, which include Dominica, Grenada, been equally conspicuous. Mature rain forests have a Guadeloupe, Martinique, Montserrat, Nevis, Saba, St. clean, uncluttered floor.

88 THE AMERICAN BIOLOGY TEACHER, VOLUME 41, NO. 2, FEBRUARY 1979 ,S '

-~~~~~~~~~~~~~~~~ .

FIGURE3. Bridgetownin Barbados.A seasonalforest island is more FIGURE4. Colleague EdwardHavis and his wife, Geraldine,in a

level and drierthan a rainforest island. plantationruin on Antigua. Downloaded from http://online.ucpress.edu/abt/article-pdf/41/2/86/36865/4446484.pdf by guest on 26 September 2021

The Effectof EuropeanOccupation During the On the shore, quiet beaches and a drierforest edge would have existed. The beaches would have reflected 17th and 18th Centuries the blacklava sand; the vegetationwould have been sun- Plantations.The influenceof Europeancivilization on parchedand scrub. Such a description also appliesto the biologicalcommunity has occurred in three stages. what exists on the shores of remote islands today. The firstwas a clearingof the lowlandsfor sugarplanta- Human life would have existed in the form of Carib- tions, whichoccurred on a massivescale in the 17thand Amer-indians. Another group, the Arawaks, were gone 18thcenturies. This was accompaniedby the even more when Columbusvisited (Biemiller1978). destructiveclearing of forests to supplyfuel for process- The seasonally forested islandwould have been less ing the sugar. To a lesser extent, the changes necessi- impressive to Columbus, but they are certainly unique in tated by cotton fields and tobacco fields caused their own way. Anquilla,Antigua, Barbados, Barbuda, ecologicaldegradation. In the 19th century,the agricul- St. Barthelemy,St. Eustasius, and St.Maartinare sea- turaleconomy in these islandsreceded, and some of the sonal forest islands.Depending upon the season when landbegan to revertto whateventually might be its virgin he arrived, Columbus might have noticed the topo- state. Such changes occur slowly. It is estimated that graphy.sdmetThese Prmtv islands, uawhich rusdo not haveol the o highaebemoun- Barbados,a seasonal rainforest, was 50%forested when tainsabe ofo thex strain nhse forests, lands are dry much of the year. For Columbusdiscovered it. Now it is less than 1%forested. example,only a smallportion in the center of Barbados Dominica, on the other hand, the oldest and largest receives over 80 inches of rain; the rest of the island islandwith the most inaccessiblemountain terrain, is still receives less than 60 inches. Most of this rainfalls in the over half forested. earlypart of the fall,leaving the islanddry the remainder Grazing.Grazing has had a horriblydestructive effect of the year. on the lowlandsof the largeislands and on the savannas The beaches of whitecoral sand wouldhave looked as of the smallerislands. Use of the landfor grazing followed they do today. The center of the islandwould have had the declineof the sugar industry.Goats stillroam freely deciduous trees, but the land just above the beaches throughoutthe islands,eating everything in sight. I was would have been a savanna in pre-Columbustimes. told in Antiguathat goats are kept as pets; they are also Columbusprobably did not encounter much human used to supplymilk and milkproducts, skins, and meat. activity on these islands because life was simply Their voracious habits are most evident from the too difficultfor people. Archaeologistshave found few roadside. excavationalsites on these islands,and when sites are On St. Lucia,the lowlandsthat surroundthe central found, it appears that humanoccupation lasted briefly mountains are heavily used for pasture. The local (Olsen 1974). governmentviews cattle-grazingas a potentialsource of The desert coral islands, Aruba, Curacao, and income, and it is beingdone on an ever-increasingscale. Bonarie,are very flat and dry. Theirseasonal rainfallis Whatused to be rainforest and savannabecame planta- scant. As a result,the areas resembledesert withscrub, tion and now has become grazing pasture. Unfortu- brush, thorny bushes, and cacti. The beaches in Pre- nately, nature continues to be the loser. Many fragile Columbiantimes would have been much as they are plant species that evolved in rain forests and savannas today-coral white and crystallinefrom wind-swept salt may become extinct because of uncontrolledgrazing. This problemhas its roots in the earlierindifference of plantationowners. In the 1600sthe Europeansexploited

LESSER ANTILLES 89 these islands;they did not attemptto study or preserve tourists. Let us hope that as the numberof visitorsto them. these islandsincreases, the growingtourist industry will Introduced Wild Animal Species. Imported animal be heldin check by governmentpolicies based on sound species have also caused biologicaldisruption on the principlesof conservation. islands.When I inquiredabout a catlikeanimal that ran across the road in Martinique,my guidetold me it was a References mongoose. In an effortto controlthe very largeand de- structive rat population,plantation owners brought the ASIMOV,I. 1964. A short history of biology. New York: The NaturalHistory Press. mongoose to the islands. The rat problem itself was BIEMILLER,C. 1978. The islands-their history. St. unknownuntil the Europeanships anchoredor became Thomas: VirginIsland Playground, Project Three, Inc. shipwreckedin the Caribbean.Without competition or CARLOZZI,C. 1968. Conservationand Caribbeanregional predators,the ratpopulation soared. The mongoosewas progress. St. Thomas, U.S. VirginIslands: The Antioch not, unfortunately,instructed regarding its dietarymis- Press. DARWIN,C. 1960. The originof species. New York: The sion, and it devoured any accessible mammal, bird, New AmericanLibrary of WorldLiterature. reptile,and amphibian.Many snakes who playa role in DOYSCHER,R. 1976. A lesson in ecology from Hawaii. the control of rodent and insect populationswere also Science Review, MDSTA Science Service Journal 37:2. affected.Dogs, cats, and even monkeysplayed a partin MACMILLANCARIBBEAN. 1974. Atlas for Barbados, Downloaded from http://online.ucpress.edu/abt/article-pdf/41/2/86/36865/4446484.pdf by guest on 26 September 2021 the extinction of many endemic birdspecies (Carlozzi Windwards,and Leewards.London: Macmillan Education Limited. 1968). MOORE,R. 1974.Evolution. New York:Time-Life Books. OLSEN, F. 1974. Indian Creek: Arawak site on Antigua. Oklahoma:University of OklahomaPress. Preservingthe Natural History of the Lesser RICHARDS,P.W. 1964. The tropicalrain forest: an ecologi- Antilles cal study. Cambridge:Cambridge University Press. SCOFIELD,J. 1975. ChristopherColumbus and the new So extensivewas the effectof plantationactivity on the worldhe found. National Geographic 148:85. CaribbeanIslands 200 years ago that one can use the numberof old forts, shipyardruins, and decayed man- sions as indicesof islandprecipitation. The ruinsexist in Erratum direct proportionto the amount of agriculturalwealth accumulated.One fact is irrefutable:no amountof effort In the Decemberissue of AmericanBiology Teacher, can undo the past harm and biologicalabuse to which partof figure1 in RichardJ. Stevens's article,"Discrep- these islandswere subjected.Old ruinsare everywhere. ancies in Student Evaluationsof UniversityTeaching Antiguaand Barbadosabound with the ghosts of those Quality,"[40(9):546], was omitted.The figureas it should responsiblefor past naturalhistory atrocities. Estimates have appearedon page 537 is shown below. are that 40%of human-causedextinction has occurredin We apologize for any inconvenienceour error may the Caribbean(Carlozzi 1968). Fortunately, if leftundis- have caused for Dr. Stevens or our readers. turbed, nature can make a comeback. Because of the TheEditorial Staff species extinctionthat resultedfrom lack of concern for conservation and human ignorance, the islands will 3.4" never returnexactly to theirformer condition. Neverthe- u less, there is encouraging evidence that ecological LT wounds are healing. The flora in the rain forests of Guadeloupe,Dominica, and Martiniqueis endemicand 0 thriving.The CaribbeanIslands are still,in fact, breath- takinglybeautiful. Forest reserves now exist to protect U. the essential watersheds on the larger islands. The > governmentsof Barbadosand St. Vincenthave created nature sanctuaries. Many of the islands have laws, (U ~~~~~~3.714.5 though they are often poorlyenforced, to protect birds 0 1.0 2.0 3.0I- 4.0 -5.0 and fish. SFE Rating - - - One last personalobservation: it is not difficultto pre- dict another problemin the very near future-tourism. -< 4 - ~ Amplification of Variation The islandeconomies need the touristdollars and vigor- ous campaignsfor visitorsare underway.Tourism fos- 0 25 50 75 88 100 ters commercialism that can quickly become a ComputerRepresentation of PercentileRanking destructiveenterprise. Right now the islandsare attrac- FIGURE1. Distributionof UWGBFaculty SFE Ratings for "Organi- tive because of their naturalresources, but unchecked zation."(Plotted from "Percentile Norms for UWGBCCQ." UWGB commercialismcan destroy the very qualitiesthat draw Officefor EducationalDevelopment.)

90 THE AMERICAN BIOLOGY TEACHER, VOLUME 41, NO. 2, FEBRUARY 1979