Triadic Positions of Tibetan Macaques Huddling at a Sleeping Site

We studied huddling of Tibetan macaques (Macaca thibetana) at a sleeping site in Huangshan, China, during the mating and birth seasons. Tibetan macaques in a free-ranging group made physical contact with each other and formed huddling groups on the ledge of a steep cliff at night. We analyzed the size and composition of huddling groups and the frequencies of dyadic huddles—two individuals in physical contact—in the huddling group to determine the social influences on huddling behavior. Affiliated dyads that frequently groomed in the daytime frequently formed dyadic huddles in night-time huddling groups. Female–male dyads formed dyadic huddles less frequently than expected. In addition, Tibetan macaques chose 2 partners with which they initiated contact when they approached a huddling group. The frequencies with which some combinations of 3 individuals contacted each other and formed triangular huddles are not consistent with the expected frequencies. For example, female–male–male triads frequently formed triangular huddles in the birth season but did so infrequently in the mating season because of male competition for estrous females. When all 3 dyads within a certain triad formed dyadic huddles frequently, the triad was more likely to form a triangular huddle. The choices of approaching individuals might make a systematic, rather than random, positioning of individuals in huddling groups at their sleeping site.     

Spatiotemporal Analysis of Predation by Carabid Beetles (Carabidae) on Nematode Infected and Uninfected Slugs in the Field

The dynamics of predation on parasites within prey has received relatively little attention despite the profound effects this is likely to have on both prey and parasite numbers and hence on biological control programmes where parasites are employed. The nematode Phasmarhabditis hermaphrodita is a commercially available biological agent against slugs. Predation on these slugs may, at the same time, result in intraguild predation on slug-parasitic nematodes. This study describes, for the first time, predation by carabid beetles on slugs and their nematode parasites on both spatial and temporal scales, using PCR-based methods. The highest nematode infection levels were found in the slugs Deroceras reticulatum and Arion silvaticus. Numbers of infected slugs decreased over time and no infected slugs were found four months after nematode application. The density of the most abundant slug, the invasive Arion vulgaris, was positively related to the activity-density of the carabid beetle, Carabus nemoralis. Predation on slugs was density and size related, with highest predation levels also on A. vulgaris. Predation on A. vulgaris decreased significantly in summer when these slugs were larger than one gram. Predation by C. nemoralis on slugs was opportunistic, without any preferences for specific species. Intraguild predation on the nematodes was low, suggesting that carabid beetles such as C. nemoralis probably do not have a significant impact on the success of biological control using P. hermaphrodita.     

The use of electrophoresis in the separation of two closely related species of terrestrial slugs

The pattern of variation of non-specific esterases, revealed by the use of disc electrophoresis, was used in an investigation of the specific difference between Limax flavus and L. pseudoflavus. The isozyme patterns were used to differentiate between the two taxa both qualitatively and quantitatively. The results were in agreement with the results from studies of the variation in the morphology of the distal portions of the genitalia and of external body colouration and patterning. The biochemical methods allowed a rapid estimation of the difference between the two taxa and were more precise than the use of colour variation.     

A putative Ariadne-like ubiquitin ligase is required for Dictyostelium discoideum development

The Dictyostelium rbrA gene encodes a putative Ariadne ubiquitin ligase. rbrA⁻ cells form defective slugs that cannot phototax. Prestalk cell numbers are reduced in rbrA⁻ slugs, and these prestalk cells do not localize to the tip of slugs. Chimeric slugs containing wild-type cells could phototax and form fruiting bodies.     

Formation of In Vitro Mixed-Species Biofilms by Lactobacillus pentosus and Yeasts Isolated from Spanish-Style Green Table Olive Fermentations

The present work details the in vitro interactions between Lactobacillus pentosus and yeast strains isolated from table olive processing to form mixed biofilms. Among the different pairs assayed, the strongest biofilms were obtained from L. pentosus and Candida boidinii strain cocultures. However, biofilm formation was inhibited in the presence of d-(+)-mannose. In addition, biofilm formation by C. boidinii monoculture was stimulated in the absence of cell-cell contact with L. pentosus. Scanning electron microscopy revealed that a sort of “sticky” material formed by the yeasts contributed to substrate adherence. Hence, the data obtained in this work suggest that yeast-lactobacilli biofilms may be favored by the presence of a specific mate of yeast and L. pentosus, and that more than one mechanism might be implicated in the biofilm formation. This knowledge will help in the design of appropriate mixed starter cultures of L. pentosus-yeast species pairs that are able to improve the quality and safety of Spanish-style green table olive processing.     

Chloroplasts as functional organelles in animal tissues

The marine gastropod molluscs Tridachia crispata, Tridachiella diomedea, and Placobranchus ianthobapsus (Sacoglossa, Opisthobranchia) possess free functional chloroplasts within the cells of the digestive diverticula, as determined by observations on ultrastructure, pigment analyses, and experiments on photosynthetic capacity. In the light, the chloroplasts incorporate H¹⁴CO₃^- in situ. Reduced radiocarbon is translocated to various chloroplast-free tissues in the animals. The slugs feed on siphonaceous algae from which the chloroplasts are derived. Pigments from the slugs and from known siphonaceous algae, when separated chromatographically and compared, showed similar components. Absorption spectra of extracts of slugs and algae were very similar. The larvae of the slugs are pigment-free up to the post-veliger stage, suggesting that chloroplasts are acquired de novo. with each new generation.     

Relative larvicidal potentiality of nano-encapsulated Temephos and Imidacloprid against Culex quinquefasciatus

Encapsulation of temephos ranging from 1% to 16% and imidacloprid from 1% to 8% within biodegradable and biocompatible, polyethylene glycol in different ratios was done by using melt-dispersion method. The efficacy of encapsulated forms was evaluated and compared with their non-capsulated forms against larvae of Culex quinquefasciatus. The encapsulated temephos was more toxic than the encapsulated imidacloprid with LC₅₀ values of 0.013, 0.010 and 0.003 mg/L after 24, 48 and 72 h, respectively. No doubt, the non-capsulated temephos and imidacloprid were more effective as compared to their encapsulated forms. However, the same mortality rate was achieved by the slow release of lesser amount of pesticides after encapsulation, e.g., 0.003 mg/L for 8% temephos formulation and 0.019 mg/L for 4% imidacloprid as compared to their non-capsulated form of temephos and imidacloprid (0.004 and 0.021 mL/L) after 72 h of exposure. Thus, encapsulated forms are more economical and eco-friendly due to controlled slow release of their nanoparticles.     

Shape of,and body direction in,huddles of Japanese macaques (<Emphasis Type="Italic">Macaca fuscata</Emphasis>) in Arashiyama,Japan

We studied huddles of Japanese macaques (Macaca fuscata) in the Arashiyama E troop at the “Arashiyama Monkey Park, Iwatayama” of Kyoto, central Japan. The macaques made physical contact with other individuals and formed huddles when the air was cold. The 99–101 adult females and 26–36 adult males in the study troop formed 345 huddles during 42 scan samples in the winter of 2001 and 376 huddles during 52 scan samples in the winter of 2002. The average size of huddles was 2.3 (range 2–7) individuals. Males huddled less frequently than females. Maternal kin-related dyads formed 2-female huddles more frequently than unrelated dyads. Choice of huddling partners might restrict the size of huddles. The most frequently observed 3 and 4-member huddles were triangular and diamond-shaped. Macaques usually huddled ventro–ventrally, ventro–laterally, and ventro–dorsally. A third individual frequently placed the ventral part of its body against the first individual and simultaneously put the lateral part of its body against the second individual, so that the 3 individuals formed a triangular huddle. This behaviour indicates that Japanese macaques choose their position and body direction in the huddle to reduce the area of body surface exposed to the air, thereby conserving body heat.     

Multi‐locus sequence types of Campylobacter carried by flies and slugs acquired from local ruminant faeces

Aims: To assess whether flies and slugs acquire strains of Campylobacter jejuni and Campylobacter coli present in local ruminant faeces. Methods and Results: Campylobacter was cultured from flies, slugs and ruminant faeces that were collected from a single farm in Scotland over a 19‐week period. The isolates were typed using multi‐locus sequence typing (MLST) and compared with isolates from cattle and sheep faeces. Campylobacter jejuni and Camp. coli were isolated from 5·8% (n = 155, average of 75 flies per pool) and 13·3% (n = 15, average of 8·5 slugs per pool) of pooled fly and slug samples, respectively. The most common sequence type (ST) in flies was Camp. coli ST‐962 (approx. 40%) regardless of the prevalence in local cattle (2·3%) or sheep (25·0%) faeces. Two positive slug pools generated the same ST that has not been reported elsewhere. Conclusions: Despite their low carriage rate, flies are able to acquire Campylobacter STs that are locally present, although the subset carried may be biased when compared to local source. Slugs were shown to carry a previously unreported Campylobacter ST. Significance and Impact of the Study: This study has demonstrated that flies carry viable Campylobacter and may contribute to the transfer of STs within and between groups of animals on farms. Further, they may therefore present a risk to human health via their contact with ready‐to‐eat foods or surfaces.     

The slug parasitic nematode Phasmarhabditis hermaphrodita associates with complex and variable bacterial assemblages that do not affect its virulence

Phasmarhabditis hermaphrodita is a nematode parasite of slugs that is commercially reared in monoxenic culture with the bacterium Moraxella osloensis and sold as a biological molluscicide. However, its bacterial associations when reared in vivo in slugs are unknown. We show that when reared in vivo in slugs, P. hermaphrodita does not retain M. osloensis and associates with complex and variable bacterial assemblages that do not influence its virulence. This is in marked contrast to the entomopathogenic nematodes that form highly specific mutualistic associations with Enterobacteriaceae that are specifically retained during in vivo growth.     

Oscillations in stomatal conductance: the influence of environmental gain

It is supposed that oscillations in stomatal conductance are associated with the dynamic properties of the loop in which rate of evaporation affects, through physiological processes, the aperture of stomata and stomatal aperture in turn affects rate of evaporation. It is therefore predicted that their occurrence must be influenced by the magnitude of what is termed environmental gain: the sensitivity of rate of evaporation to change in leaf conductance to vapor transfer. Two methods of manipulating gain, and their effects on stomatal behavior in cotton (Gossypium hirsutum L. cv. Deltapine Smooth Leaf), are described. In the first, gain was increased by decreasing ambient humidity; in the second, it was made zero by regulating ambient humidity to keep rate of evaporation constant despite changes in conductance. The results are in accord with the supposition.     

The acceptability of meadow plants to the slug Deroceras reticulatum and implications for grassland restoration

Background and Aims

Despite the selective pressure slugs may exert on seedling recruitment there is a lack of information in this context within grassland restoration studies. Selective grazing is influenced by interspecific differences in acceptability. As part of a larger study of how slug–seedling interactions may influence upland hay meadow restoration, an assessment of relative acceptability is made for seedlings of meadow plants to the slug, Deroceras reticulatum.

Methods

Slug feeding damage to seedling monocultures of 23 meadow species and Brassica napus was assessed in microcosms over 14 d. The severity and rate of damage incurred by each plant species was analysed with a generalized additive mixed model. Plant species were then ranked for their relative acceptability.

Key Results

Interspecific variation in relative acceptability suggested seedlings of meadow species form a hierarchy of acceptability to D. reticulatum. The four most acceptable species were Achillea millefolium and the grasses Holcus lanatus, Poa trivialis and Festuca rubra. Trifolium pratense was acceptable to D. reticulatum and was the second highest ranking forb species. The most unacceptable species were mainly forbs associated with the target grassland, and included Geranium sylvaticum, Rumex acetosa, Leontodon hispidus and the grass Anthoxanthum odoratum. A strong positive correlation was found for mean cumulative feeding damage and cumulative seedling mortality at day 14.

Conclusions

Highly unacceptable species to D. reticulatum are unlikely to be selectively grazed by slugs during the seedling recruitment phase, and were predominantly target restoration species. Seedlings of highly acceptable species may be less likely to survive slug herbivory and contribute to seedling recruitment at restoration sites. Selective slug herbivory, influenced by acceptability, may influence community-level processes if seedling recruitment and establishment of key functional species, such as T. pratense is reduced.     

Sex Differences in Thermogenesis Structure Behavior and Contact within Huddles of Infant Mice

Brown adipose tissue (BAT) is a thermogenic effector abundant in most mammalian infants. For multiparous species such as rats and mice, the interscapular BAT deposit provides both an emergency “thermal blanket” and a target for nestmates seeking warmth, thereby increasing the cohesiveness of huddling groups. Sex differences in BAT regulation and thermogenesis have been documented in a number of species, including mice (Mus musculus)–with females generally exhibiting relative upregulation of BAT. It is nonetheless unknown whether this difference affects the behavioral dynamics occurring within huddles of infant rodents. We investigated sex differences in BAT thermogenesis and its relation to contact while huddling in eight-day-old C57BL/6 mouse pups using infrared thermography, scoring of contact, and causal modeling of the relation between interscapular temperature relative to other pups in the huddle (T_IS ^rel) and contacts while huddling. We found that females were warmer than their male siblings during cold challenge, under conditions both in which pups were isolated and in which pups could actively huddle in groups of six (3 male, 3 female). This difference garnered females significantly more contacts from other pups than males during cold-induced huddling. Granger analyses revealed a significant negative feedback relationship between contacts with males and T_IS ^rel for females, and positive feedback between contacts with females and T_IS ^rel for males, indicating that male pups drained heat from female siblings while huddling. Significant sex assortment nonetheless occurred, such that females made more contacts with other females than expected by chance, apparently outcompeting males for access to each other. These results provide further evidence of enhanced BAT thermogenesis in female mice. Slight differences in BAT can significantly structure the behavioral dynamics occurring in huddles, resulting in differences in the quantity and quality of contacts obtained by the individuals therein, creating sex differences in behavioral interactions beginning in early infancy.     

WATER-REGULATORY BEHAVIOUR IN TERRESTRIAL GASTROPODS

1. Terrestrial snails and slugs are exceedingly susceptible to dehydration due to evaporative water loss from the integument and lung surface, and the deposition of a dilute mucous trail. Active slugs can lose 30–40% of their initial body weight (IBW) within 2 h. 2. Both field and laboratory studies have revealed that habitat selection by snails and slugs is well correlated with the availability of water. In addition, numerous species display homing behaviour, returning directly to their moist secluded daytime resting sites at dawn. 3. Several aspects of locomotor activity are affected by body hydration and environmental conditions such as relative humidity. Moist conditions result in termination of aestivation in snails and a generally higher level of activity in both snails and slugs. In contrast, severe dehydration initiates aestivation in snails and an increase in the intensity and duration of circadian locomotor activity in slugs. 4. Huddling behaviour is a specialized example of the general preference of slugs for moist habitats. When groups of slugs are exposed to dry environmental conditions, they form closely packed aggregations. This response results in a decrease in the rate of dehydration of the individual slugs. 5. When slugs have been dehydrated to about 90% IBW, rhythmic closures of the pneumostome are initiated. As dehydration progresses there is a reduction in the open diameter of the pneumostome. These responses reduce the total exposure of the lung surface and thereby evaporative water loss. In slugs dehydrated to about 80 % IBW, these responses can result in a 7 % reduction in water loss. 6. When slugs have been dehydrated to about 65% IBW (67·6 ± 4·3% IBW) they move on to a moist surface, assume a characteristic flattened posture and remain quiescent while water is absorbed through the surface of the foot. Once they are rehydrated (to 93·5 ± 12·4% IBW) they move off the moist surface. Thus there exists a specific dehydration threshold for the initiation of contact-rehydration and a rehydration set-point at which the response is terminated. 7. Both initiation and termination of contact-rehydration are controlled by variations in haemolymph osmotic pressure. The behaviour can be experimentally initiated by injection of hyperosmotic mannitol solution and terminated by injection of dilute saline. 8. Contact-rehydration involves bulk flow of water through an epithelial paracellular pathway in the integument of the foot. The rate of absorption of [¹⁴C]inulin during contact-rehydration is similar to that of water. The efficacy of water movement through the pathway is modulated by body hydration, the pathway being opened only in dehydrated slugs. 9. By means of the dual-limit control of contact-rehydration slugs can behaviourally regulate their body hydration and haemolymph osmolality within the tolerable hydration range described by the upper and lower limits.     

Acquired Phototrophy through Retention of Functional Chloroplasts Increases Growth Efficiency of the Sea Slug Elysia viridis

Photosynthesis is a fundamental process sustaining heterotrophic organisms at all trophic levels. Some mixotrophs can retain functional chloroplasts from food (kleptoplasty), and it is hypothesized that carbon acquired through kleptoplasty may enhance trophic energy transfer through increased host growth efficiency. Sacoglossan sea slugs are the only known metazoans capable of kleptoplasty, but the relative fitness contributions of heterotrophy through grazing, and phototrophy via kleptoplasts, are not well understood. Fitness benefits (i.e. increased survival or growth) of kleptoplasty in sacoglossans are commonly studied in ecologically unrealistic conditions under extended periods of complete darkness and/or starvation. We compared the growth efficiency of the sacoglossan Elysia viridis with access to algal diets providing kleptoplasts of differing functionality under ecologically relevant light conditions. Individuals fed Codium fragile, which provide highly functional kleptoplasts, nearly doubled their growth efficiency under high compared to low light. In contrast, individuals fed Cladophora rupestris, which provided kleptoplasts of limited functionality, showed no difference in growth efficiency between light treatments. Slugs feeding on Codium, but not on Cladophora, showed higher relative electron transport rates (rETR) in high compared to low light. Furthermore, there were no differences in the consumption rates of the slugs between different light treatments, and only small differences in nutritional traits of algal diets, indicating that the increased growth efficiency of E. viridis feeding on Codium was due to retention of functional kleptoplasts. Our results show that functional kleptoplasts from Codium can provide sacoglossan sea slugs with fitness advantages through photosynthesis.     

Invertebrate biodiversity affects predator fitness and hence potential to control pests in crops

Natural enemies that control pests usually allow farmers to avoid, or reduce, the use of pesticides. However, modern farming practices, that maximize yields, are resulting in loss of biodiversity, particularly prey diversity. Does this matter? Pests continue to thrive, and without alternative prey the predators should, perforce, concentrate their attentions upon the pests.We showed that a diverse diet significantly enhances predator fecundity and survival. Experiments were conducted using common generalist predators found in arable fields in Europe, the carabid beetle Pterostichus melanarius (Coleoptera: Carabidae) and the linyphiid spider Erigone atra (Araneae: Linyphiidae). We tested the hypothesis that mixed species diets were optimal, compared with restricted diets, with respect to parameters such as predator weights, egg weights, numbers of eggs laid, egg development times, egg hatching rates and predator survival. In carabids, an exclusive earthworm diet was as good as mixed diets containing earthworms for egg production and hatching, but less good than such mixed diets for increase in beetle mass and sustained egg laying. For spiders, aphids alone (Sitobion avenae) or with the Collembola Folsomia candida, drastically reduced survival. Aphids plus the Collembola Isotoma anglicana improved survival but only aphids with a mixed Collembola diet maximized numbers of hatching eggs.Predators offered only pests (slugs or aphids) had lowest growth rates and fecundity. We therefore demonstrated that conservation of a diversity of prey species within farmland, allowing predators to exploit a diverse diet, is essential if predators are to continue to thrive in crops and regulate agricultural pests.     

Compensatory feeding response of the slug Sarasinula plebeia to dietary dilution

Summary Like many polyphagous herbivores, individuals of Sarasinula plebeia (Fischer) (Soleolifera: Veronicellidae) consume a variety of plant species that may differ in nutritional content. In this study we determined the ability of these slugs to compensate for such variation in diet composition. Dilution with water of an agar-based diet containing commercial guinea pig food or carrot root to obtain dry weights (dw) of 90, 70, 40 and 10% of diet fresh weight (fw), caused immature slugs to consume increasingly more fresh weight of food [as much as 4.7-(guinea pig) to 6.1-fold (carrot) more]. Dry weight consumption and body mass-relative dry weight consumption rate also increased at intermediate dilutions, buth with further dilution, dry weight intake declined despite the greater fresh weight consumption. At each dilution level, slugs fed the guinea pig diet consumed from ca. 5-to 6.4-fold more fresh weight than the carrotfed slugs. The former grew substantially, with their final biomass and body mass-relative growth rate varying curvilinearly with diet % dw. If these slugs had not fed more but instead maintained the same fresh weight consumption as slugs in the 90% dw tretments, without altering food utilization efficiencies, then their biomass gain in the 70, 40 and 10% dw treatments would have been only about 62, 43, and 21%, respectively, of the values actually attained. In contrast, carrot-fed slugs did not grow and were only able to maintain their initial biomass. For each diet, slug tissue water (% fw) was highest in the most diluted treatment but did not differ significantly among the other dilution levels. Approximate digestibility of the carrot diet was highest at intermediate dilution levels (ca. 75% of ingested food was digested and absorbed); for the guinea pig diet, this efficiency declined linearly from about 66% to 59% with increased dilution. For slugs that grew (i.e., those fed the guinea pig diet), effeciences of converting digested (29–52%) and ingested (18–33%) food to dry biomass were both curvilinearly related to diet % dw. Thus, S. plebeia, like many other herbivores, has the capacity to increase food consumption substantially inresponse to reduced dietary nutrient level, allowing the slugs to cope with variable nutrient content in their food plants.     

Comparison of sister species identifies factors underpinning plastid compatibility in green sea slugs

The only animal cells known that can maintain functional plastids (kleptoplasts) in their cytosol occur in the digestive gland epithelia of sacoglossan slugs. Only a few species of the many hundred known can profit from kleptoplasty during starvation long-term, but why is not understood. The two sister taxa Elysia cornigera and Elysia timida sequester plastids from the same algal species, but with a very different outcome: while E. cornigera usually dies within the first two weeks when deprived of food, E. timida can survive for many months to come. Here we compare the responses of the two slugs to starvation, blocked photosynthesis and light stress. The two species respond differently, but in both starvation is the main denominator that alters global gene expression profiles. The kleptoplasts'' ability to fix CO₂ decreases at a similar rate in both slugs during starvation, but only E. cornigera individuals die in the presence of functional kleptoplasts, concomitant with the accumulation of reactive oxygen species (ROS) in the digestive tract. We show that profiting from the acquisition of robust plastids, and key to E. timida''s longer survival, is determined by an increased starvation tolerance that keeps ROS levels at bay.     

Dispersal movements of non-native and native terrestrial slugs in an urban environment

Animal movement varies from undirected dispersal to directed migration. Movement rates may have implications for conservation and resource management, as well as pest control, and they play a key role in invasion success. In slugs, long-distance dispersal is typically passive, whereas active movement is critical for local dispersal and determines access to resources such as food and shelter. Telemetry has recently been used to study individual slug movements in the wild, whereas movement in arena tests has explored mechanisms of interspecific competition and invasiveness in slugs. Studies that relate the performance of individual slugs in arena tests to their post-release behavior in nature are lacking. We measured individual short-term movement speed of commonly occurring native and non-native slugs of the genera Arion and Limax in arena tests and tracked their post-release dispersal movements in a garden by PIT telemetry. We demonstrate clear differences in movement behavior among the species, but non-native slugs did not display higher movement rates than their native congeners. In the arena test, slugs of the genus Limax displayed a higher short-term speed than slugs of the genus Arion, whereas in the field, individuals of Limax maximus showed lower dispersal rates compared to the other slug species. Moreover, there was a positive correlation between short-term speed in the arena test and movement in the field among individuals of L. cinereoniger, indicating the possible existence of behavioral syndromes in slugs, which may link movement ecology, animal personality, and the invasion ecology of pest species.     

Niche overlap of mountain hare subspecies and the vulnerability of their ranges to invasion by the European hare; the (bad) luck of the Irish

Niche conservatism is the tendency of related species to retain ancestral tolerances after geographic separation. We used Ecological Niche Modelling and Principal Components Analysis of bioclimatic and habitat variables to describe the extent of the species niche, and degrees of bioclimatic–habitat niche conservatism within the mountain hare (L. timidus) clade. Mountain hare niche space was contrasted with that of the European hare (L. europaeus), to shed light on species interactions in contact zones throughout Europe. All five subspecies of mountain hare had quantifiably distinct niches. Fennoscandian (L.t. sylvaticus, L.t. timidus) and highland (L.t. scoticus, L.t. varronis) subspecies, however, were most similar, exhibiting greatest apparent niche conservatism. They inhabit tundra, boreal forest and uplands, and, hence are presumed most similar to the ancestral form. The Irish hare was distinct, being consistently distinguished from other mountain hares in both 2D and nth dimensional (4D) niche space. The ecological distinctiveness of the Irish hare provides further evidence that it is an Evolutionarily Significant Unit, particularly vulnerable to displacement by introduced European hares with which it competes and hybridises. Projections under global climate change suggest that, by 2070, bioclimatic space for invasive European hares in Ireland will expand (by 79%) but contract for endemic Irish hares (by 75%), further facilitating their replacement. The near complete species replacement of the heath hare (L.t. sylvaticus) in southern Sweden, where the European hare has also been introduced, may suggest a similar fate may be in store for the Irish hare.