Vampire Shrews

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Kingdom: Animalia, Sub-kingdom: Metazoa,
Phylum: Chordata, Sub-phylum: Vertebrata,
Class: Mammalia,
Sub-class: Theria, Infra-class: Eutheria,
Order: Insectivora,
(Sub-order: Liptophyla, Super-family: Soricoidea,)
Family: Soricidae,
Sub-family: Draculinae


The ‘Vampire Shrews’ or (to use an alternative name for them that is less commonly applied, but technically more accurate...) ‘ Climbing Shrews’ presumably evolved from a lineage of “conventional”, ground-dwelling shrews whose members took to climbing in bushes & other vegetation in search of their invertebrate prey, probably during some warmer & wetter period of Earth’s history when such food was even more abundant in those places than it is today. No fossils that can definitely be identified as belonging to any intermediate species have been discovered so far, apart from a few teeth whose attribution to this group is still a matter of dispute in some quarters, but that’s hardly unusual for land-dwelling animals of such a relatively small size. Their differences from the ‘soricines’ (the modern “conventional”, ground-dwelling shrews) include not only feet that are better-adapted for grasping vegetation (and the fur of larger animals, too) — as well as, in two species whose ancestral lines seem to have developed this feature separately from each other, a prehensile tail — but also changes in the nature of the venomous saliva: The traits that they share with the ‘soricines’, in addition to the basic “shrew” shape, include the possession of glands located on their sides that secret a substance which makes them unpalatable to many potential predators.
The four species that exist within this sub-family today fall into two distinct groups, each of which has expanded its ancestral diet and thus survived into the present day — despite there having been a decline in the invertebrate food-supply in their habitats, and increased competition for this from other groups of animals, since that likely origin — whereas any related lines that remained purely “insectivorous” in nature have apparently died out. The members of the genus Draculinus, which are the three species of ‘True Vampire-Shrews’, now feed to differing extents on blood from other mammals of various sizes, which may be considerably larger than themselves — and sometimes from birds, too — as well as on smaller animals, whilst the ‘Tree-Creeper’ or ‘False Vampire-Shrew’ which is the only known member of the genus Dendrosorex has become much more of a generalised omnivore and has even added tree-sap as a major constituent in its range of staple foods (thus, one might say, becoming “vampiric” on trees…).


Common, or ‘Ruddy’, Vampire-Shrew


Binominal name: Draculinus sanguinis
Range: lowland areas in ‘Bears Armed’, and possibly in other parts of the IDU as well
Habitat: undergrowth & scrub, preferably damp, and to a lesser extent long grass; also temporarily on the outsides of large mammals
Status: numbers diminishing due to persecution, but not actually “threatened” yet

Physical Details

Head & Body: 5.0-9.0cm
Tail: 3.5-4.8cm
Weight: 4.5-16.0g
Teeth: 2.1.1.2/2.0.1.2
Colour: brown or reddish-brown, paler underside

Food and Habits

Food: mammals’ blood, invertebrates & other small vertebrates
Nest: grasses, underground
Behaviour: alternatively active and resting throughout 24 hours; feeds on invertebrates in vegetation and more rarely on the ground, and sometimes on other small vertebrates (mainly on the ground) too; will climb onto larger mammals in order to drink their blood, and may also attack sleeping mammals of quite large size on the ground
Voice: high-pitched squeaks
Hibernation: none
Migration: may travel aboard mammalian prey, otherwise none

Life Cycle

Litters: usually 2 or 3 per year, in nest
Young: 4 to 8, naked and helpless
Maturity: normally year following birth
Longevity: usually 1-2 years

Comments


This is the species of ‘Vampire-Shrew’ for which the blood of other mammals is probably most important overall as a source of food. Although it forages for invertebrates and other small vertebrates to some extent, both on the ground and by climbing up into the vegetation, it feeds for preference by clambering aboard larger mammals when these brush against the plants in which it’s climbing and then — after snapping up any smaller parasites that it might encounter along the way, which was probably what the common ancestors of all this genus’s member species originally climbed onto other mammals to do — making a small wound through a suitable location in their skin and lapping the blood that flows out of this. They are assisted in this behaviour by the fact that their venom, rather than being a paralytic agent as is that of the ‘soricine’ shrews, forms a mixture of a (“local”) anaesthetic and an anti-coagulant. The main species upon which they feed in this way are Deer (of all kinds, up to & including ‘Elk’/‘Moose’), Woods Bison and other bovids, Sivatheres, feral Donkeys, and domestic livestock. They are less likely to attack those animals whose diets typically include significant proportions of meat, such as Dogs & Wolves, Tigers, pre-sapient Bears, or sapient ‘Ursines’, presumably making this decision on the basis of smell, which is a trait that may have been selected for evolutionarily because any of them that do try this are more likely than those preying on herbivores to be noticed and killed... The thick skin and usual habits of Wild Pigs also render these animals reasonably safe from attack. The shrew will often normally leave each “host” quite shortly after taking a meal there, returning to nearby plants as soon as this then becomes possible, which is made easier by the fact that they often choose vegetation close to streams & pools in which to hunt and can therefore transfer to & from those “hosts” as the latter pass through these areas on their way to & from those sources of drinking water: This habit means that breeding females are able to resume feeding on mammalian blood rather than on invertebrates quite soon after giving birth, because they will usually be able to return from this feeding in time to nurse their young again before it’s too late.


Least Vampire-Shrew


Binominal name: Draculinus minimus
Range: lowland areas & middle altitudes in ‘Bears Armed’, and possibly in other parts of the IDU as well
Habitat: undergrowth & long grass, preferably damp; & also on the outsides of large mammals
Status: not threatened

Physical Details

Head & Body: 3.6-6.1cm
Tail: 2.5-4.2cm, prehensile
Weight: 1.5-6.2g
Teeth: 2.1.2.2/2.0.1.2
Colour: dark brown, whitish underside

Food and Habits

Food: invertebrates, mammals’ blood, other small vertebrates
Nest: woven from grasses, above ground-level
Behaviour: alternatively active and resting throughout 24 hours; feeds on invertebrates both in vegetation and on the ground, and more rarely on other small vertebrates (mainly on the ground) too, but will also climb onto larger mammals that pass through the vegetation where it lives in order to drink their blood and may remain aboard them for a long time
Voice: high-pitched squeaks, sometimes ultrasonic
Hibernation: none
Migration: may travel aboard mammalian prey, otherwise none

Life Cycle

Litters: up to 4 per year, in nest
Young: 4 to 10
Maturity: about four months
Longevity: probably less than 2 years

Comments


This species of ‘Vampire-Shrew’ typically hunts for its invertebrate prey in long grasses and other plants that are less sturdy than the sorts of bushes which its ‘Common’ (and rather larger) relative favours: Transferring onto large mammals tends to be more difficult in these circumstances, so that when a Shrew of this species does manage to board a suitable host it generally remains riding (& feeding) on it for some time — preferably in a location where the skin is relatively thin and there’s something besides just fur to hold onto, such as at the bases of the ears — instead of dismounting again after a single meal… However they will also readily board, feed once from, & then leave, animals that are noticeably smaller than those favoured by that relative — including young members of those “large mammal” species, as well as adults of types that don’t get that large such as Rabbits and Hares — when the opportunity to do so arises. Adult females will normally refrain from attacking mammals in these ways while they have an unweaned litter in the nest, because of the fairly high risk that their “prey” will carry them too far away from these for them to return in time to give those young their next feed, and rely on finding invertebrates — and perhaps vertebrates of various kinds that are small enough for them to kill outright, too — during these times: However they are capable of ‘delayed implantation’, meaning that they can postpone the effective start of pregnancy for some time after mating and thus perhaps wait until they’re well-nourished before facing this strain on their metabolism. The venom of this species is also, like that of their larger relative, a mixture of a (“local”) anaesthetic and an anti-coagulant.


Worst Vampire-Shrew


Binominal name: Draculinus horridus
Range: lowland areas in ‘Bears Armed’, and possibly in other parts of the IDU as well
Habitat: undergrowth & scrub, preferably damp, and long grass; also sometimes on the outsides of large mammals; may invade farmyards and houses in winter
Status: declining, due to persecution

Physical Details

Head & Body: 5.9-11.2cm
Tail: 3.4-5.3cm
Weight: 10.2-28.8g
Teeth: 2.1.2.2/2.0.1.3
Colour: greyish-brown, paler underside

Food and Habits

Food: invertebrates & other small animals, mammals’ blood, carrion
Nest: usually a burrow that was dug by some other animal
Behaviour: alternatively active and resting throughout 24 hours, although probably more active at night than in daytime in most cases; feeds mainly on the ground, although also to a lesser extent up in the vegetation; may also climb aboard passing mammals in order to drink their blood, but is more likely to attack them from the ground while they’re asleep — or sometimes even, for the members of smallish species such as Rabbits and Voles, while they’re awake — in which case it may eat their flesh as well as drink their blood
Voice: high-pitched squeaks, may hiss when startled or when males are arguing
Hibernation: none
Migration: generally none, although it may wander in search of food, but if population in an area builds up beyond a certain point or a natural disaster strikes then mass emigration may occur

Life Cycle

Litters: usually 1 but up to 3 per year, in nest
Young: 2 to 4, less helpless than those of the other Draculinus species
Maturity: normally year after birth
Longevity: usually 2-3 years

Comments


Although not much longer on average than its ‘Common’ relative, this type of Shrew is somewhat more sturdily built and much more of an active predator (rather than just a blood-drinking ecto-parasite) than that species. In some ways it looks like an intermediate form between the other Draculinus species and the ‘soricine’ or “conventional” shrews, because it is less well adapted to climbing than either of its genus’s other members whilst its venom is more strongly paralysing but less effective an anti-coagulant than theirs: However there are also various other, less obvious details of both its anatomy and its genes that do place it firmly within this group. The relatively uncommon occasions when it climbs from vegetation onto large mammals in order to drink their blood feed are likely to involve the very largest of the possible “prey” species around, because their size & the fact that they usually move more slowly than the “lesser” beasts maximises the time available for that transfer whilst they’re probably a bit less likely than the smaller beasts to notice the Shrew’s presence on their surface, although injured or infirm animals of other kinds may also be attacked in this way: Its preferred method of approaching members of these species is along the ground while they’re sleeping (or are awake but seriously incapacitated). The fact that its venom doesn’t encourage the flow of blood from wounds as effectively as does the venom of its smaller relatives means that it has to make larger, more ragged wounds in its larger targets in order to obtain enough food from them. When it can’t find suitable targets from amongst the larger mammals it actively seeks out rodents and other small vertebrates instead, as well as the invertebrates that are more frequent constituents of a typical ‘Insectivore’ diet, sometimes ambushing them from twigs that are a few inches above the ground and sometimes going down into their burrows — despite the inherent risk involved in possibly meeting adult members of larger species such as rabbits or voles head-on in such confined spaces — too… There have even been a few reports of it being found in moles’ tunnels, although whether that was actually to hunt the moles or just to raid their larders remains unknown so far. Although they normally don’t hunt together it’s not actually unknown for a member of this species that which finds an immobile animal that’s too large for them to tackle alone, such as a deer with a broken leg or a domestic animal confined in a pen to announce this (by, as was only recently discovered, a special, ultrasonic squeak) to any others who might be in earshot so that they can share in paralysing it in exchange for a share in the food: This behaviour seems to be the most likely during migrations. Shrews that have a large corpse on which to feed may tunnel into it, both to seek out the sections that they prefer and to gain shelter from larger predators until they leave that site, which can be rather a surprise for any other scavengers that start feeding on occupied remains: There are even stories of them tunnelling into sleeping people, and killing these by eating their hearts, but these would seem to be only stories*. They are regarded as a danger to domestic livestock, especially when this is being kept in pens or sheds, and when they invade houses they may also attack not just pets but people too… For people to die as a result of their attacks is extremely rare but has been verifiably documented in a few cases, most of which involved either young children or elderly & infirm individuals who were anaesthetised or even paralysed whilst asleep and then bled to death from the wounds that the Shrews caused without waking up. There have also been some instances, although again only very rarely, when susceptible individuals have suffered fatal allergic reactions to the Shrew’s venom. Fortunately, however, it does not [yet] seem to have become a vector for diseases. The fact that this species’ hunting patterns tend to involve more wider-ranging travel than those of the related species has led them to evolve into producing young that are more advanced than their relatives’ at birth, so that they can leave the nest sooner, although this has been at the cost of their producing a reduced number of offspring per litter.


Tree-Creeper (False Vampire-Shrew)


Binominal name: Dendrosorex draculoides
Range: lowland areas & middle altitudes in ‘Bears Armed’, and possibly in other parts of the IDU as well
Habitat: deciduous woodland & thick scrub, orchards
Status: fluctuates, but probably fairly stable overall

Physical Details

Head & Body: 4.5-7.0cm
Tail: 3.8-6.6cm, prehensile
Weight: 10.8-32.0g
Teeth: 2.1.3.3/2.0.1.3
Colour: mostly light brown, whitish underside

Food and Habits

Food: invertebrates, tree-sap, nectar, fruit, other small vertebrates, birds’ eggs
Nest: holes in trees, sometimes deserted birds’ nests
Behaviour: primarily crepuscular & nocturnal, but may also have periods of activity during the day; almost entirely arboreal
Voice: squeaks
Hibernation: yes, usually late autumn to early spring, in nest
Migration: none

Life Cycle

Litters: 2 to 4 per year, in nest
Young: 4 to 8
Maturity: year after birth
Longevity: usually 1-2 years

Comments

The members of this species have feet that are even better adapted to climbing than are those of any Draculinus species, and with the prehensile tail added they are capable of quite incredible agility up in the branches, but they are far less likely than any of their relatives to visit the ground. They differ from the “True” Vampire-Shrews in being non-venomous, and although they have retained the scent-glands on their flanks that make shrews in general highly distasteful to most predators these have a weakened effect that doesn’t always protect them from [e.g.] Crows… Having developed stronger incisors than their relatives they are able to pierce the bark on trees’ branches, both to get at any insects that might be present there and to release flows of sap which they then lap up: The ‘Sugar Maple’ is therefore one of the species that they especially favour as homes, which is definitely NOT appreciated by the ‘Ursines’ who also harvest those trees’ sugary sap even though the Shrews usually feed only from the thinner, upper &/or outer branches (because their teeth can’t pierce the bark on the thicker ones) and thus don’t directly affect the supply “upstream” where the Ursines tap the trees’ trunks. They are regarded as a pest in orchards too, because of the damage that they inflict on the fruit, and even more so in silk-producing areas because there they will feed not only on the mulberries but on the actual silkworms as well.
There is some competition for food with Dormice (with which they may sometimes be confused, if not seen clearly), but these two types of animal are able to retain populations in the same areas as each other because each of them has both advantages and disadvantages that the other lacks: The Tree-Creeper’s ability to feed on tree-sap in spring & summer combines with its higher birth-rate to let it build up its numbers more quickly than Dormice can do during years when the weather is good , but then the Dormice’s ability to feed on nuts (whose shells are too tough for the Shrews’ smaller & more pointed teeth to handle) in later seasons combines with their greater size to mean that a higher proportion of them than of the Shrews are likely to survive hibernation through the harsher winters…


(* like the old stories from the real world about ‘soricine’ shrews allegedly doing this…)