How Many Butterfly Species Are in Ghana?
Total Page：16
File Type：pdf, Size：1020Kb
HowHow manymany butterflybutterfly speciesspecies areare inin Ghana?Ghana? The Afrotropical Region is second only to KnownKnown ButterflyButterfly SpeciesSpecies inin thethe WorldWorld the Neotropics (i.e., Central and South byby BiogeographicBiogeographic RegionRegion America) in terms of the number of NeotropicalNeotropical 80008000 butterfly species that occur. Ghana has AfrotropicalAfrotropical 38003800 about 900 species. Over ⅓ of these OrientalOriental 27002700 described species are considered rare or PalearcticPalearctic 20002000 very rare. It is estimated that about 5% of Papuan/AustralianPapuan/Australian 10001000 Ghana’s butterfly species, those that are NearcticNearctic 700700 especially rare, have yet to be discovered. Ghana’s butterflies are overwhelmingly forest-dwelling species (~730 of 900). Most forest butterfly species generally do not venture far (if at all) into non-forested areas. Most savanna or open habitat butterfly species do not venture far (if at all) into forested areas. The butterflies you see around Bobiri guesthouse are a mixture of open habitat species and forest species. Salamis parhassus, the Forest Mother-of- Pearl. This is one of Ghana’s largest and Bobiri Forest Reserve is an example of the moist semi- most beautiful species. The upper wing surface is silvery-white and is cast with a purplish sheen. It is a generally common deciduous forest habitat subtype (the other subtypes species and can often be seen flying in are wet evergreen, moist evergreen, and dry semi- the forest. deciduous). Some of Ghana’s forest butterflies do not occur at Bobiri because they require wetter conditions. Nearly 500 butterfly species have . been documented in Bobiri forest. Additional species likely exist here and would be uncovered from more exhaustive surveys of the forest. WhyWhy createcreate aa butterflybutterfly sanctuary?sanctuary? Forest reserves in Ghana Ghana’s forests are among the most critically imperiled in the world and Bobiri also among the most biologically go To unique. It is estimated that 80-90% of original forest cover has been destroyed. Virtually no forest cover remains outside existing forest C o t e reserves. Some reserves no longer d Forest reserve condition ’ I v o 1 Excellent i r even have any forest left. As forest e 2 Good 3 Partly degraded habitat disappears, so too do forest 4 Mostly degraded 5 Poor dependent species, such as Bobiri’s From: Hawthorne & Abu-Juam (1995) Forest Protection in Ghana. IUCN Publ. No significant forest forest butterflies. Bobiri butterfly sanctuary was the brainchild of Dr. Joe Cobbinah, Director, Forestry Research Institute of Ghana, and Dr. Mike Wagner, Professor, Northern Arizona University, USA. This sanctuary was created to provide 1) protection for the species that live here, 2) an income source, which helps promote sustainable use of forest biodiversity, and 3) a place where Ghanaians and foreign nationals alike can learn about and enjoy the country’s unique and beautiful forest communities. WhatWhat dodo butterfliesbutterflies eat?eat? Most butterflies take in nourishment by sucking fluids through their proboscis or “tongue”. You are probably most familiar with the nectar feeders, that is, the butterflies that visit flowers. But many butterflies do not feed on nectar. About ¼ of Ghana’s butterfly species never visit flowers. These species feed, instead, on rotting or fermenting fruit. The large majority of fruit-feeding species in Ghana are forest dependent species. You will cause many of these to “startle up” as you walk along the forest trails. Did you know that some butterflies actually also feed on excrement and/or animal carcasses? Many butterflies also puddle on wet sand or mud, where they take up water, minerals, and amino Three forest species feeding on fruit that has fallen to the forest floor. Euphaedra perseis (top). Bebearia acids. Often large numbers will gather at a single mardania (bottom left) and Bebearia zonara (bottom right). spot and fly up en masse when disturbed. The two individuals below belong to the family, Lycaenidae. Members of this family are nectar feeders and are very small. The many types of tiny butterflies you see flying at Bobiri are Lycaenids. In fact there are more Lycaenids in the world then any other type of butterfly. Nearly ⅓ of Ghana’s butterflies are Lycaenids. Papilio nireus male puddling along the road to Bobiri Butterfly Sanctuary. This is a common forest species that visits flowers. The wings on the upper side of this butterfly are black and traversed by The male of Nepheronia thalassina is a beautiful duck’s-egg-blue. bright green bands; hence, its common name, the These are common visitors to the flower gardens at Bobiri. Narrow-Banded Green Swallowtail. WhyWhy dodo unrelatedunrelated speciesspecies looklook alike?alike? Many butterfly species resemble each other in color and pattern. This is known as mimicry and results slowly over time from natural selection. Non toxic species mimic (resemble) species that are toxic or taste bad. Predators then avoid both species even though the mimetic species could be eaten without harmful results. Ghana has Some mimetic species many mimetic species. Papilio found in Ghana. ABOVE: Papilio dardanus male (top dardanus, a common visitor to flowers left) and P. dardanus female (top right). Amauris niavius (bottom left) and P. at Bobiri,is a spectacular example of dardanus female (bottom right). RIGHT: Left column, mimicry. P. dardanus males all look the top to bottom: Acraea vestalis male, Acraea same, but there are at least 14 different macaria male, Acraea alcinoe female, Acraea female forms in sub-Saharan Africa all epaea male, Acraea epaea female ... Right column: Five different mimetic forms of which resemble unrelated species! of Pseudacraea eurytus. ButterflyButterfly BehaviorsBehaviors Butterflies display a number of interesting behaviors, many of which are associated with finding and selecting a mate. Males locate females either by patrolling areas where females feed or lay eggs, or by perching along “flyways” in wait. Perching males will vigorously defend their space by “fighting” and actively chase other males away. Mating often involves a series of Euriphene barombina (above) is a common fruit-feeding forest butterfly at Bobiri. The male is easily recognizable because of behaviors in which the male “courts” the its distinctive blue color and set of white dots. Females are brown and orange with a white stripe across the forewing and female. Few females in nature are unmated look nothing like the males. Euphaedra medon (below) is another very common fruit-feeding forest species. There are approximately 75 Euphaedra species in West Africa. Both of because males will check out any butterfly these males are “perched” on plants in sunny spots along one that fits a basic image and attempt to mate of Bobiri’s trails. with any female of the right species. In some species males will even collect on the pupal case or chrysalis of a female and wait for her to become an adult and emerge. Only the most competitive male gains access to the female. You may see a butterfly flying from plant to plant after briefly alighting on leaves of each. Butterflies “taste” with their “feet” and this is a female searching for the appropriate host on which to lay an egg. ABOVE LEFT: Bebearia zonara male courting a B. zonara female. The male is hovering near the female, rapidly fluttering his wings. Intermittently, he will make physical contact by “shoving” the female. He is likely giving off pheromones (sex hormones) during the whole courting process. If she is receptive, they will mate. ABOVE CENTER: Kallimoides rumia, the African Leaf Butterfly, perched in typical position, i.e., head down on broad leaves about 2-3 meters above the ground. K. rumia is fond of palm wine and this particular individual is hanging out at one of the palm wine-tapper’s camps in the forest ABOVE RIGHT: Palla decius perched on a tree along the main Bobiri road. P. decius is a member of the Charaxinae subfamily. The Charaxinae are large, robust, strong flying butterflies that are especially attracted to excrement. CreditsCredits The current checklist of butterfly species at Bobiri was compiled by Dr. Torben Larsen (left) in conjunction with research for his book, Butterflies of West Africa (Apollo Books, Svenborg, Denmark, October 2005). Dr. Larsen also provided the plates depicting examples of mimicry. The photo of Nepheronia thalassina, was shot by Sky Stephens. The photographer of the Larsen photo is unknown. All other photos are by the author, J. L. Bossart, who also assumes responsibility for any factual errors. Rose-Hulman Institute of Technology (Terre Haute, IN, USA) graciously printed these posters free of charge..