Hedgehog Declines: Are Badgers to Blame?
Two of Britain’s most adored mammals, the Badger (Meles meles) and Hedgehog (Erinaceus europaeus) are never far from the headlines in recent times, though for starkly contrasting reasons. Badgers it seems are public enemy number one, at least to some. Indeed, following a dramatic population increase, Badgers are now subject to a controversial cull in an effort to halt the spread of bovine tuberculosis, with some arguing that the cull may benefit more than just ailing cattle.
Unlike the Badger, which has made the press due to a increase in numbers and the associated implications of such a rise, Hedgehogs have achieved coverage for an entirely different reason. Yes, whereas Badger numbers have risen in recent years, Hedgehogs have plummeted,their population crashing from an estimated 36 million in the 1950’s to less than one million today. The reasons for this seem clear; habitat loss, traffic collisions and farming practices often cited as possible catalysts. Some however have suggested a different explanation for this worrying trend; that Badgers may in fact be a driving factor in decline of the Hedgehog. This is a subject that has been touched on frequently in recent years, with many articles published on the matter including those here, here and here. Some, it seems, seek to justify the current Badger cull through its supposed benefits to our besieged Hedgehogs while others dispute this notion most virulently. Are Badgers really to blame for the decline of the Hedgehog in the UK? If not entirely, are they playing their part and as such, are culls justified? I certainly do not have the answers but, reading up on the matter, it does make for an interesting debate.
Badgers eat Hedgehogs, that is a fact.
Whatever your thoughts on the matter, it is impossible to deny that Badgers are a natural predator of Hedgehogs. Though both Foxes (Vulpes vulpes) and Domestic Dogs have been shown to kill Hedgehogs, in Europe this species has only two main predators; the Eagle Owl (Bubo bubo) and the Badger. With Eagle Owls rare in the UK, the Badger is widely considered to be the main predator of Hedgehogs both in Britain and Northern Europe (Hubert et al, 2011). Indeed, most Badger dietary assessments from Europe, including that of Goszczynaski et al (2000) show Hedgehogs to feature in the diet of Badgers – though it should be stressed that nowhere, to the best of my knowledge, are Hedgehogs a dominant prey item; Earthworms, rodents, vegetable matter all taking precedence. Still, Hedgehogs are taken to a varying degree and Badger/Hedgehog depredation is by no means a rare occurrence.
Do Badgers impact upon Hedgehog populations?
Badgers do indeed have the potential to impact upon Hedgehog populations, particularly in rural areas (Hof & Bright, 2009). In Britain, where under the right circumstances, badger density can reach 30-40 individuals per square kilometer (Macdonald & Newman, 2002) it has been shown that Hedgehog abundance naturally varies in direct relation to the abundance of Badger setts (Michol et al, 1994). In addition to this, it has also been shown that female Hedgehogs tend to avoid areas with a heavy Badger presence (Dowding, Harris & Baker, 2010) while Doncaster (1992) concluded that Badgers impacted upon Hedgehog dispersal in their study of an introduced Hedgehog population. Finally, Hubert et al (2011) also observed reduced reproductive success in rural Hedgehogs hailing from areas with a comparably low Badger density – thus it stands to reason that in Britain, where Badgers are more numerous, such an effect could be amplified. It should also be noted however that some studies dispute the aforementioned findings, most notably a five year study by the University of Nottingham set up to examine the causes of Hedgehog deaths in a semi-rural environment. Here it was found that the majority of ‘Hogs died as a result of human activity with traffic collisions accounting for 51% of fatalities. Indeed, only one Hedgehog was killed by Badgers..
In the UK Hedgehogs have been shown to be more abundant in urban areas as opposed to rural settings, something that has been attributed to the lower abundance of Badgers in urban environments (Hof & Bright, 2009). Indeed, in Britain studies have shown Hedgehog numbers to stand somewhere in the region of 20-70 individuals per square km compared to upwards of 80 in urban areas (Doncaster, 1992; Morris, 1988; Reeve, 1994). With British cities still holding relatively few Badgers it stands to reason that Hedgehog declines in urban areas can be attributed to other factors such as the alteration of gardens and traffic collisions. It should be noted that urban badgers are however becoming more common, something which could lead to conflict further down the line with urban hedgehog populations already depleted due to the aforementioned factors.
In addition to direct depredation, Badgers may also impact upon Hedgehogs through competition for food. Both species are indeed partial to Earthworms and a Badger may consume five times more in one sitting than a Hedgehog. This however is likely to only pose a problem in exceptional circumstances and thus does not warrant much concern.
Would a Badger cull help Hedgehogs?
Evidence from the initial pilot culls in 2014 has shown, that at some sites, Hedgehog numbers did increase following the removal of Badgers. Something that makes sense given the predator/prey relationship observed between the two species, and a fact that has lead to some advocating badger culls as a way of conserving Hedgehogs. Removing predators is a tried and tested way to conserve prey species and though many may not like it, increased control of Badgers likely would benefit Hedgehogs – Perhaps more so in rural areas given the findings of Hof & Bright (2009) etc.
Despite these results however many organisations including the British Hedgehog Preservation Society (BHPS) and the People’s Trust for Endangered Species (PTES) have voiced their concern over such a notion. In a joint statement, both organisations reiterated the need to combat the other factors attributing to Hedgehog declines, stressing a need to focus on the conservation of Hedgehogs in urban areas by creating hedgehog friendly towns and through the removal of barriers that prevent foraging. Both organisations stand fully opposed to the present badger cull, writing:
None of the scientific evidence supports the idea that culling badgers is an effective means of controlling bovine TB in the field. Recent pilot culls (2013, 2014) failed to kill sufficient animals for the cull to have been effective (despite extending the length of the trial) and raised doubts about the humaneness of the method. Given this, BHPS and People’s Trust for Endangered Species (PTES) join leading wildlife scientists in arguing against a cull of badgers to control bovine TB. Indeed, scientific evidence suggests that culling badgers may make the TB situation worse, a further reason why PTES/BHPS would not advocate culling badgers to benefit hedgehogs”.
The Badger vs Hedgehog debate really is a tricky one, both species comprising iconic figments of the British landscape. At present I remain firmly on the fence in regards to the “cull or not to cull debate“. The present Badger cull does not sit well with me, not because of ethics – Indeed I freely support many species control schemes but simply due to the limited facts showing that culling makes any real difference to bovine TB levels. This said, Hedgehogs are likely to benefit from the control of badgers, as shown by the pilot culls thus I would find it hard to dispute such actions should further research be produced highlighting a negative relationship between the species. Like it or not, Badger culls are a reality at present and this provides the perfect opportunity for research into the relationship between the two species. With culls set to roll out across new areas, research into Hedgehog populations should surely follow. If widespread increases are noted, I may well have to reevaluate my neutral stance. I do however find it important to combat the arguably more pressing issues associated with Hedgehog declines first, before pointing the finger at a natural predator.
Badgers and Hedgehogs have coexisted in harmony for millennia and it is only now, due to factors such as habitat loss and traffic, that they have come into conflict. These factors surely kill far more Hedgehogs each year than Badgers and are undoubtedly responsible for weakening populations to such an extent that depredation by a natural predator becomes a problem. While things are indeed being done to conserve Hedgehogs in urban areas, things look less promising in the countryside – Something that may lead to a ‘discussion’ about Badgers in the future. Until then however I look forward to seeing every option explored and hopefully, a conclusion reached that benefits both species.
Image Credit: Badger, By kallerna – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=20438654. Hedgehog by James Common, Own work.
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