Recently I had the opportunity to read Hans Kruuk’s ‘The Social Badger: Ecology and Behaviour of a Group-living Carnivore’ (1989).
It made me wonder some more about the badger social organization and its dependence on resource distribution and local resource abundance.
I am familiar with the resource dispersion hypothesis but as far as I understand, it has not been confirmed precisely in European badgers, i.e., when resources become scarcer with respect to their sparser distribution on the landscape, badger territories, indeed, become larger but the changes in their abundance do not necessarily modify group size.
That is to say, when resource abundance within the badger social group territory decrease, the group size does not decrease in linear correspondence but, firstly, badger individual foraging grounds begin to overlap within the group and also the territories of different badger groups begin to overlap to a greater extent.
Interestingly, with increased overlap of resource use within the group’s territory, badgers probably have to forage closer to one another and, at the same time, they decrease the socializing intensity within the sett (they begin sleeping more apart from one another).
In my view, these findings correlate with other considerations, for example, the results of studies (Robertson, A. et al., 2014) evaluating individual foraging niche occupied by badgers within their social groups, i.e., the fact that group members do not appear to share all of the resources but also they are not aggressively restricted from using all the group’s resources.
Instead, individual badgers within the group simply seem to enjoy foraging on their own and using their own favourite patches that probably might contain slightly different resources (or, if not resources, then nutrient concentrations due to these patches being in different locations).
I have discussed this in another post (Possible reasons behind individual foraging specialization in European badgers) where I attempt to proposition that badgers, as a ‘newly social species’ might find it difficult to socialize constantly and it might be important to them to differentiate between ‘us time’ (at sett) and ‘me time’ (while out foraging) in order to reduce energy expenditure associated with cognitive effort.
Badgers seem to prefer solitary feeding over collective foraging and they also enjoy utilizing ‘their own resources’ (carving out a niche within their social group) while the affable social interactions (bonding) are constricted to the sett (sleeping together, allogrooming, grooming, allomarking, marking, playing etc.).
Additionally, I find it curious that sometimes badgers might exchange their social group for the neighbouring group (irrespective of breeding intents) and there have been cases where some badgers even navigate between two neighbouring groups.
In these cases, it seems that badgers first begin foraging in the neighbouring territory, then sometimes sleeping over and eventually, they might move out of their current group and into the neighbouring group.
Meanwhile, badgers are also highly territorial and they fight intruders (including neighbours) to injury or even death.
Then how it is possible that sometimes intruders are tolerated and sometimes not?
I believe that all of these findings lead to one conclusion – social living in badgers is not limited merely by resource dispersion/abundance but it also based on the ability by group members to stick to a solitary feeding routine that does not interfere with the routine (including the use of favourite patches) observed by other badgers in the group.
It appears to me that while foraging, badgers enjoy order and the aforementioned routine, and tradition as well as sticking to olden golden foraging methods.
They do not like inventing new strategies and if they can, they would obtain most of their prey/forage through the same techniques (hoovering them up without much digging or chasing if possible).
While feeding, badgers seem rather conservative, and I find it likely that aggression between group members or between badgers from different groups arises not just when some badgers intrude into other badgers’ territory but when they intrude into what might be called ‘personal space’.
I believe that badgers get along in the group (with regard to being able to share a territory) if every badger is capable of selecting their favourite foraging patches and if they do not feel crowded during their foraging bouts.
Also, it might be of crucial importance that they can stick to their own individually-elaborated routines and traditions.
As long as these favourite patches, routines and traditions are not under threat, badgers might tolerate other badgers on their territory perhaps even including neighbouring individuals.
It might be that neighbouring individuals are allowed to join the new group if they find a way to fit in the group’s foraging scheme (by ‘scheme’ I would mean the distribution of favourite patches and the visitation of these patches following some order etc.).
If the newcomer (or a current group member) does not intrude into the individual badger’s ‘me time’ and ‘personal space’, they are not chased off aggressively or they are chased off less aggressively.
Thus, the group membership might depend on the ability to carve out one’s own niche in a manner that allows for everyone in the group to feel that they are solitary foragers.
While feeding, badgers might want to move around and use resources in a way that resembles a solitary use of territory.
If the badger is not disturbed by other badgers (who are in their own favourite patches during their selected time), they might be still living under impression (psychological, not physical) as if they are the exclusive territory owners.
Thus, badgers might be forming territories within territories, and these territories would befall within the group’s territory.
What matters for the badger would not be the actual exclusivity of the territory but the spatial and temporal isolation which can be achieved even while sharing the territory with other badgers.
To make a comparison, we also adjust our schedules and habits within households, offices and other social settings in order not to interfere with others (this would be especially true of the use of bathroom in the morning) and if we have adapted successfully, we might barely meet one another and we would never get to have to wait in the line or to become otherwise aggravated that we have to share resources (e.g., electric coffee pot, our favourite mug etc.).
We still have to share space but out efficient timing and planning of spatial activities allows us to avoid one another to the point that we can still feel we are ‘the kings of our castle’.
Conflicts might arise when this ‘subjective impression’ is breached and when someone suddenly shows up in a patch where the badger was about to feed at the time.
Badgers might not want to experience much of the unexpected during foraging which is also demonstrated by their lack of flexibility in foraging strategies (while, curiously, attesting to great flexibility regarding the (seasonal and regional) use of varied resources).
The unexpected and spontaneous interactions might be reserved for the sett, and if badgers are forced to share their foraging space and time with other badgers due to scarcer resources, they might want to introduce more of that solitary living element into their life at sett (decreasing the amount of interactions, e.g., choosing not to sleep together).
Partly, this might be due to the aforementioned weariness that comes with greater cognitive effort (as I have explained in the former post).
If badgers have to tolerate other badgers while out foraging, they might not have enough energy and patience to tolerate them back at the sett, as well.
There might be other reasons which I hope to address in future posts.
However, I believe that this might explain why a decrease in resource abundance within the group’s territory is not necessarily and directly correlated with a decrease in group size.
It might not be the resource abundance itself which determines tolerance level and group size.
It might be the ability to use resources in a manner which prevents intrusion by other badgers into any one individual’s ‘me time’ and ‘personal space’.
If badgers have to use overlapping foraging grounds but they can still figure out how not to get into anybody’s way, the group size might not decrease at once.
It might be the frequency and intensity of these breaches (that force the individual badgers to be at all times aware they are sharing a territory without the comfortable and pleasant illusion that they are alone in the world while feeding) that determines when social tension arises and when group size has to become reduced.
Similarly, acceptance of ‘strangers’ (neighbours) might be the result of the ability (or fortune/misfortune) of these strangers to befit into the invisible order set by the group.
This would be suggestive of a different perception of territoriality and it would be interesting to see whether individual badgers defend their specific favourite patches more intensely than their group territory in general.
Of course, badgers have territorial boundaries and perhaps they have a sense of group’s territory but it is also possible that the group’s territory in European badgers is founded on individual and subjective perception of the interconnectedness of ‘one’s own resources’ within that territory in order to keep up one’s own niche within their group.
Group territoriality might be coincidental to this individual niche-based territoriality.
In many respects, badger societies should be studied in order to learn the perfect balance between privacy (including private ownership) within a society that demands for collective interests and collective use of land (while insuring against resource overexploitation).
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I should also note that as breeding females appear to be dominant in badger societies, their use of resources might be more determinant of cohabitation than the use of resources by other group members (some group members might be more flexible in their use of territory than other group members).
References
Kruuk, H. The Social Badger: Ecology and Behaviour of a Group-living Carnivore (Meles Meles), Oxford University Press, 1989, ISBN 0198587031, 9780198587033
Robertson, A., McDonald, R.A., Delahay, R.J. et al. Individual foraging specialisation in a social mammal: the European badger (Meles meles). Oecologia 176, 409–421 (2014). https://doi.org/10.1007/s00442-014-3019-2
Notes by Ieva 