Scat # 1 was found slightly off the main trail in a dry gravelly area beside a large thorny bush some 2.5 meters high. There appeared to be small rabbit-sized runs through the undergrowth leading away from the find site but no tracks were visible in the hard, dry substrate.
The length of Scat # 1 is approximately 20cm. It is thicker at one end, tapering to a thin narrow point at the other. On examination the scat is made up of two distinct parts; a thicker segment consisting mainly of vegetable matter, including blades of grass and a piece of dried, hard wood approximately 1cm square whilst the thinner segment is greyer in colour and appears to consist of hardened clay-like material. The whole scat is slightly twisted and contains hairs along it’s full length, both black and tawny brown. The two distinct parts are joined by hairs into one single unit. Although desiccated and bleached in colour by long exposure to the sun the scat retained a musty odour that was more pronounced when broken up.
Identifying the scat presented some problems, the most obvious being my very poor local knowledge. Prior to holidaying on the island I had no idea which mammals were present on Menorca, either endemic or introduced. With the help of field-guides and the online European Mammal Assessment resource this can be overcome and possible species either ruled in or out. That the scat contained both vegetable and animal remains would point to an omnivorous animal although it should be noted that animals primarily thought to be carnivores can consume plant material throughout the year and that the diet of a species and the subsequent morphology of scat can alter markedly depending on habitat and prey.
With this in mind it is possible to begin to make educated deductions regarding the origin of Scat # 1. Scats joined together in “chains” linked together by hairs are characteristic of the Red Fox (Vulpes vulpes) however the European Mammal Assessment centre shows that the Red Fox is absent from Menorca. Badgers (Meles meles) have an omnivorous diet that could produce such a scat and being a mustelid may also produce scat of a similar shape and size to Scat # 1 however Badger are known to prefer to deposit waste in regular well-used latrine sites rather than singularly and as with the red fox the badger is not recorded on Menorca. I would also argue that we can also rule out that the scat was deposited by a domestic dog – unless Menorcan dogs are in the habit of eating wood and grass and producing scats that are unlike any seen in Britain.
The twisted texture and narrowing, tapering shape of Scat # 1 point to a mustelid and Schreiber et al describe an interesting introduction of Genets and Pine Martens to the island of Menorca, (Weasels, Civets & Mongooses – an action plan for the conservation of Mustelids and Vivverids; A Schreiber, R Wirth, M Riffel & H Van Rompaey. IUCN/SSC Mustelid and Vivverid Specialist Group).
Ibiza and Menorca each have a distinctive population of the small-spotted genet (G. genetta). It is sometimes thought that the species’s occurrence there (as well as to the European mainland) is due to introduction by man. If so, these introductions have presumably originated from geographically separate populations and the genet has changed in morphological characteristics in its new European habitats. There is also an undescribed form of beech marten (Martes foina) on Ibiza and a subspecies of pine marten (Martes martes minoricensis) on Menorca, both of which are distinctive from mainland animals (Delibes in litt. 1987). The Menorca small-spotted genet is believed to be still common. However, the Menorca marten and the Ibiza small-spotted genet are classified as “Rare” by ICONA (1986). The Ibiza beech marten might have become extinct recently. Surveys are needed to assess the status of these animals and to draw up management recommendations.
Could Scat # 1 be from the introduced Menorca Pine Marten (Martes martes minoricensis)? Schrieber et al tell us that pine marten are “rare” on the island. The area in which the scat was recovered was on the edge of a large and protected area of scrubby coastal forest. Although in boreal and temperate environments pine marten are known to favour mature woodland with dense cover on Menorca they show no habitat preference (Clevenger, 1993 & 1994).
Eurasian pine martens are considered habitat specialists, associated primarily with mature stands of mesic mixed forest habitats, and avoid areas without overhead cover. The species is found throughout the temperate and boreal regions of the continent but on the Mediterranean island of Menorca, introduced pine martens thrive in a competitor and predator free environment. I test the prediction that because of evolved prey-capture and predator avoidance strategies Menorcan martens should select habitats most similar to temperate and northern parts of their range. Scat index routes were used to quantify pine marten habitat selection. Marten did not demonstrate any habitat type preferences although observed use of pine forests and coastal shrublands was slighly greater than expected. Marten were indifferent to overhead cover whereas mesic sites and areas of tall high shrub density were favored. Small mammal trap indices and preferred prey suggested that martens commonly used non-forested areas. My results demonstrated that on Menorca pine martens were habitat generalists. In the absence of predators open non-forested habitats were equally important to pine marten as were forested ones
Mostly active during the night and at dusk pine marten may have several nesting sites within the home range, using abandoned bird nests and rock crevices as hideaways. Home range size estimates vary widely between studies although it is clear that male ranges are larger than female ranges and that they overlap those of one or more females. Some sources give an average of 23 sq km for males and 6.5 sq km for females (Nowak 1999), others estimate only 2.2 sq km for males and 1.5 sq km for females (Zalewski et al 1995). On the island of Menorca ranges were measured as 0.5 sq km for females and 6.9 sq km for males (Clevenger 1993).
Although the pine marten is an opportunistic omnivore it favors animal food, relying on small mammals for most of the year with the composition and proportion of foods often changing according to season and local conditions, such as when fruits and berries become abundant in autumn. Scottish and Menorcan martens may fill 30% of their diet with these vegetarian resources whilst in other regions, such as Poland, fruits may never be eaten (Zalewski et al 1995, Clevenger 1993, Gurnell et al 1994). Aside from the effects of seasonally available fruits and unpredictable rodent booms, diet is otherwise reasonably constant. Favored foods include small mammals such as voles and squirrels, birds, insects, carrion, frogs, reptiles and snails. Diets of pine martens that forage along a loch in Scotland have been recorded to include crabs, echinoderms, and barnacles (Gurnell et al 1994).
The overwhelming information available on pine marten scat is from northern Europe and there is very little available in general literature regarding the composition or morphology in a Mediterranean, and specifically Menorcan, environment. A positive identification of Scat # 1 is impossible but in light of the evidence – the find site close to rabbit runs, the presence of mammal hairs – possibly rabbit - in the scat, the twisted and chain-like morphology of the scat I am inclined to the view that Scat # 1 is possibly that of the Martes martes minoricensis.
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