Butterflies of Semuliki National Park, Uganda
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Butterflies of Semuliki National Park, Uganda Scott Forbes endemism with around 98% of contain the greatest diversity of The Open University Afrotropical species and approx- butterfly species, though not imately 76% of the genera not necessarily abundance. This diversity [email protected] occurring outside the region gradually reduces with altitude. (Carcasson, 1964). The park is also confined within the Salient characteristics of narrow African equatorial belt which Semuliki National Park extends from the Atlantic at Basse Semuliki National Park has an area of Casamance in Senegal to western 219 km2 and is part of the Central Tanzania and western Kenya. This belt African Congo Basin forest system of of forest is only interrupted by the the Democratic Republic of Congo Dahomey Gap, a broad band of (DRC), being separated from the Ituri Guinean forest-savannah mosaic that forest of the DRC only by the Semliki extends to the coasts of Togo, Benin and River. It is separated from the rest of Ghana. All the lowland rainforests of East Africa by the Rwenzori Mountain Africa are restricted within this narrow range and with it being located within equatorial belt. These lowland forests the Albertine Rift (Fig. 1), the western are richer in biomass and plant species arm of the Great Rift Valley, it is than any other vegetation type in Africa included within the Eastern and subsequently provide one of the Afromontane biodiversity hotspot richest habitats for butterflies. They (Myers et al., 2000). The Afrotropical region and equatorial belt geography Semuliki National Park, a lowland rainforest in western Uganda, will become the focus of my attention for the next four years of doctorate study on its butterfly composition and conservation. It is a little-known and isolated pocket of protected tropical rainforest within Uganda’s National Park network managed by the Uganda Wildlife Authority (UWA). Considerably more famous for its birdlife, with over 400 species (Chege et al., 2002), than its insect fauna, I realised on a trip there in 2011 that here was the perfect location to undertake Afrotropical butterfly research. It is located within the biogeographic Afrotropical region (Crosskey and White, 1977), a region defined to include Africa south of the Sahara, including Madagascar and Southern Arabia. This region has approximately 4,000 butterfly species; roughly 20% of the world’s total, and is second only in species number to the Neotropical region, which has approximately 8,000 species. The butterflies of this biome show Fig ure 1. Albertine Rift Valley. remarkable regional species-level Map courtesy of the PAWAR project / Woods Hole Research Center. 82 Antenna 38 (2) Figure 2. Semliki River. Semuliki National Park is a closed The park is bordered to the south by transcribed by the administrator as canopy, moist semi-deciduous forest, the main Fort Portal to Bundibugyo ‘Semliki’ and has been retained. This with an altitude ranging from 670 m to road and to the north by the Semliki word in both guises is also used for The 760 m and is the only lowland forest in River (Fig. 2), which runs north for Semliki Wildlife Reserve which borders Uganda. There has been no accurate approximately 140 km from the Lake Albert and also for the Semuliki historical meteorological data taken for northern end of Lake Edward in the National Park (the correct spelling). the Park, but average temperature is DRC, eventually draining into Lake around 300 C and average rainfall Albert in Uganda. The river also around 1,500 mm/year. With a Central effectively divides Semuliki National Afrotropical research and African influence on its fauna and flora Park from the Ituri forest in the DRC. historical studies on the park is comprised predominantly of Long ago an inquisitive colonial Lepidoptera at Semuliki Uganda ironwood, Cynometra administrator was making his way Research on African Lepidoptera and alexandrii, with other common trees through the forest and came across an their conservation is urgently needed including the Wild Oil Palm, Elaeis as yet unnamed river. An old lady from with the present pressures for multiple guineensis, and a number of different fig the local Bakonzo tribe happened to be land use on protected land and the tree species, including Ficus vogeliana, passing with a wicker basket half full of possible effects of climate change. which provide an excellent food fish strapped around her head, so he Although it is situated within one of resource for my targeted butterfly stopped her and asked her in Swahili the most biodiversity rich regions of communities. There are small areas of what the river was called. The old lady, Africa in The Albertine Rift, this region bamboo swamp near the Semliki River not understanding Swahili, assumed also has a very high human population dominated by Mitragyna stipulosa and that this was yet another plundering density. Logistically, working with a small area of grassland covering adversary who was actually wanting to Lepidoptera in Africa also produces its approximately 75 ha enclosed within know what was in her basket, and not own personal challenges. The scarcity the forest. Areas of the park have poor wanting to tell him that she had fish of resources for field-based research, a drainage and in the rainy seasons, replied in her Lukonzo language small local research community, between March-May and Sept.-Dec., ‘semuliki, semuliki’ translating as together with climate difficulties makes these can experience extensive ‘nothing, nothing’. So the ignominious any research proposition a stimulating flooding. name was duly noted and wrongly challenge. Antenna 38 (2) 83 Research in Semuliki has been community structure with a focus on restricted in the last few decades due to understanding resource availability and instability within the region, a lack of seasonality. Subsequently, the general security and an incredibly bad introduction of a long-term access road from the nearest town, Fort collaborative monitoring programme Portal, 60 km away. The last large scale with UWA, investigating the spatial and biological survey was a Uganda Forest temporal variation of communities, Department, now National Forest would allow a greater understanding of Authority, census of its fauna and flora the park’s ecosystem and therefore in 1996 (Howard and Davenport, enable an influence on future 1996). Since 1996 small scale research management actions, especially with had amounted to a trickle of studies, respect to the butterfly communities mostly by ornithologists. An excellent present in Semuliki. new road, recently built by the Chinese, now allows access to the Park Semuliki habitat Headquarters from Fort Portal in less than 45 minutes, with the road There are no roads into the park and so continuing on to the border of the DRC. the entrances to the Park’s trails have to be accessed by foot. There are two Unlike other East African countries, main trails in the park (Red Monkey such as Kenya (Larsen, 1991) or trail, named after one of the common Tanzania (Kielland, 1990), there is no primates found in the park, and the country guide to Uganda’s butterflies. As Kirumya trail named after a nearby Semuliki has its faunistic influence from river). About 10 km apart, both trails Central Africa the excellent but now rare eventually lead to the Semliki River ‘Papillons du Zaire’ by Lucien Berger has around 14 km west of the park proved my most useful aid for field boundary road. There is a marked identification and is still also a highly difference in the forest structure accurate source of information. The story around these trails with Red Monkey Figure 3. van Someren Trap example. behind this publication, commissioned containing classic dense closed canopy being the hanging of cylindrical van by the then President of Zaire, Mobutu ironwood forest with an open Someren fruit-baited traps (Fig. 3) at Sese Seko, is a fascinating historical understorey. The forest around the various height elevations (forest floor to anecdote. Apparently, the majority of the Kirumya trail has quite extensive canopy), using fermented bananas as copies of this book that were published sections that had been allocated to the bait. These traps attracted the ended up being stored at the Mobutu surrounding local communities for frugivorous butterflies from the family palace deep in the jungle at Gbadolite as cultivation during Idi Amin’s era. With Nymphalidae, especially the large gifts for visiting dignitaries. A few copies further encroachment of the Park Afrotropical genera Bebearia, were distributed to Mr Berger for his continuing during Amin’s period and Euphaedra and Bicyclus. There were personal use and to provide for friends. beyond, all settlers were evicted from also rarer catches of Cymothoe, On Mobutu being expelled from the the Park in the early 1990’s before it Charaxes and Euriphene species. country in 1997 his palatial residence was granted National Park status in was ransacked and the remaining books 1993. In this section of the park you that he had stored were destroyed. Only can find abandoned fruit orchards and Capturing, photographing and a few copies remain and the price of a coffee or cocoa plantations and the identifying specimens copy reflects the scarcity and quality of secondary forest understorey can be The canopy traps were positioned with the book. fairly impenetrable, except with the the assistance of one of the Batwa from The Lepidoptera data from the 1996 use of a machete. Community resource the local communities. I hired the local census showed Semuliki to be the most use of the park is now allocated to a Batwa King, named Joffra (Fig. 4), whose butterfly rich park in Uganda, containing period of one day per week, when the climbing skills were impressive. He 309 species from a country with a total women of the surrounding climbed seven trees in one day of approximately 1,300 species communities can enter the forest for positioning the canopy traps at a distance (Davenport, 2001).