22 Feb Giraffes – One species or 4? Does it matter?
Author: Natalie Steiner
The world’s tallest land mammal and one of the most iconic and recognisable of all of Africa’s animals…..the giraffe. Thought to be common place and an easy spot of safari, Africa’s giraffe are in fact reaching a crucial turning point with regard to their long-term future and survival. As publicised in recent times, the global giraffe population has declined by up to 40% in the last thirty years. In 1985 there were estimated to be 151,702 – 163,452 individuals in the wild but by 2015, that had decreased to 97,562 (1). As a result of this dramatic decline, the conservation status of giraffe was amended in 2016 from ‘Least concern’ to ‘Vulnerable’ on the IUCN (International Union for Conservation of Nature) Red Data List (1).
Giraffes are geographically widespread in non-continuous, fragmented populations across much of the sub-Saharan African continent. Currently that covers a total of 21 countries(1). Their decline has been associated with differing factors throughout their range with the most serious problems being habitat loss, war & human conflict, mining and illegal poaching for traditional medicine.
A single species of giraffe (Giraffa camelopardalis) is currently recognised across Africa by the IUCN SSC Giraffe and Okapi Specialist Group (GOSG). Within that one species, there are nine sub-species (see Table 1). As a general rule, populations in West and Southern Africa are increasing and those in Eastern Africa are decreasing.
Until 5 years ago, relatively little scientific research and conservation effort had been conducted on giraffe, especially compared to other large African mammals such as elephant, rhino and lion. In 2013, the creation of the IUCN SSC Giraffe and Okapi Specialist Group helped bring the plight of giraffe to global attention and fund significant research into the species(2).
Since 2001, a number of scientific studies have proposed a variety of different giraffe taxonomies ranging from two to eight separate species (3,4,5). A study in 2016 using DNA analysis from skin biopsies reported that there are four distinct species (with five sub-species) that have not mated or exchanged genetic information for over a million years (6) – Northern, Southern, Reticulated and Masai species. The Giraffe Conservation Foundation now uses that classification for the purposes of its conservation efforts – http://www.giraffeconservation.org/giraffe-species
So why does all this matter?
For any species, conservation efforts must consider a number of factors. The number of species and sub-species recognised (by the IUCN and other scientific institutions) has a profound impact on the conservation of the global population and is therefore of great importance. The IUCN currently only recognises one species of giraffe and as such, the same conservation status of ‘Vulnerable’ is given to the species as a whole. However, if the four species classification is used, different species would have a different status with the Northern giraffe (comprising both the Nubian and West African sub-species) being listed as ‘Endangered’ due to their very low population sizes. As a first step, a broad conservation program across all 21 countries must be established to ensure long-term survival. In the meantime, the scientific community can come to a definitive agreement on classification.
The international trade in giraffe products is not currently covered under CITES as it is thought to be insignificant. It has not yet been determined whether in fact this is the case. With the increasing pressure and ban on the elephant ivory trade, instances of giraffe bone carvings (which look similar to ivory) are being detected. With the giraffe population declining so rapidly, a CITES listing could help prevent any existing (legal and illegal) trade becoming another cause of further decline. As a keystone species, across a range of African habitats, every effort must be made to reverse the trend in giraffe numbers before it’s too late for action.
It is often the case in the natural world that the more you look, the more you find. What you physically see however cannot be used as a basis for assumptions or making conservation decisions. With the continual development of scientific techniques, such as DNA analysis, we continue to learn more and more about wildlife – giraffes are a case in point – same but different!
References:
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- IUCN Red List – www.iucnredlist.org/details/9194/0 Retrieved 05-10-2017
- http://www.giraffidsg.org/home/gosg/ Retrieved 20-01-2018
- Russell, Seymour (2001). “Patterns of subspecies diversity in the giraffe, Giraffa camelopardalis (L. 1758) : comparison of systematic methods and their implications for conservation policy”. PhD Thesis, University of Kent at Canterbury
- Brown, D. M.; Brenneman R. A.; Koepfli, K.-P.; Pollinger, J. P.; Milá, B.; Georgiadis, N. J.; Louis Jr., E. E.; Grether, G. F.; Jacobs, D. K.; Wayne R. K. (2007). “Extensive population genetic structure in the giraffe”. BMC Biology. 5(1): 57. doi:10.1186/1741-7007-5-57 PMC 2254591 PMID 18154651.
- Groves, Colin; Grubb, Peter (2011-11-01). Ungulate Taxonomy. JHU Press. ISBN 9781421400938.
- Fennessy, Julian; Bidon, Tobias; Reuss, Friederike; Kumar, Vikas; Elkan, Paul; Nilsson, Maria A.; Vamberger, Melita; Fritz, Uwe; Janke, Axel (2016). “Multi-locus Analyses reveal four giraffe species instead of one”. Current Biology. 26: 2543–2549. doi:10.1016/j.cub.2016.07.036. PMID 27618261.
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