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L Lagomorpha Navigation to guide their movements in the landscape and the timing thereof. Anthony Caravaggi The order Lagomorpha is comprised of two School of Biological Earth and Environmental families, the hares and rabbits (Leporidae or Sciences, University College Cork, Cork, Ireland leporids) and the pikas (Ochotonidae). The navi- School of Biological Sciences, Medical Biology gational capabilities of lagomorphs are poorly Centre, Queen’s University Belfast, Belfast, UK understood, with the few movement studies to have been conducted focusing on dispersal, home range behavior, foraging, and habitat use. Synonyms Indeed, movement behavior has been entirely unstudied in most lagomorph species. Studying Behavior; Hare; Movement; Pika; Rabbit the navigational capabilities of small-to-medium- sized mammals can be challenging as the equip- ment required for fine-scale data collection (e.g., GPS collars) are often too heavy and/or have Definition limited battery life. For example, the maximum weight for GPS collars is defined by the size of the – Navigation the theory and practice of charting a subject. This is known as the “5% rule” (Cochran course to a remote goal (Schöne 1984). 1980); the weight of the collar should not exceed 5% of the focal animal’s mass. For a very large hare weighing 5 kg, that would equate to a GPS Introduction collar weighing 250 g. The typical battery life for such a collar is around 500 days, though that is The daily movements of animals are governed by based on the recording of only a handful of “fixes” many factors including the need to find food, (i.e., records of the individual’s location) per day – water, conspecifics, and favorable environmental not enough for nuanced analysis of movement conditions while trying to avoid predators, domi- behavior such as navigational strategies nant ecological competitors, and unfavorable hab- (Handcock et al. 2009). The frequency of fixes itats and conditions. Animals use external cues required for such studies would exhaust the bat- such as odor (Gagliardo 2013), landmarks tery in only a few days. However, technological (Baader 1996), day length (Baoping et al. 2009), advances such as the use of micro-GPS and snap- the position of the stars (Dacke et al. 2013), and shot receivers (McMahon et al. 2017), as well as the Earth’s magnetic field (Chernetsov et al. 2017) increasingly lightweight collars and improved # Springer International Publishing AG, part of Springer Nature 2018 J. Vonk, T. K. Shackelford (eds.), Encyclopedia of Animal Cognition and Behavior, https://doi.org/10.1007/978-3-319-47829-6_1164-1 2 Lagomorpha Navigation batteries, mean that many obstacles are slowly population dynamics. The benefits conferred by being overcome. It is likely that future technolog- individuals moving within and between ical improvements and dedicated research will populations and into previously uncolonized hab- lead to a greater understanding of movement itats are such that dispersal is considered to under- behavior and navigational strategies, particularly pin the persistence of many species (Avril et al. in larger lagomorphs. 2011). The causes of dispersal are poorly under- Given the lack of navigation-specific literature, stood, though it is likely that inbreeding avoid- here I broadly summarize research on movement ance, mate competition, resource availability, and behavior, particularly in the context of home the density of conspecifics all play a role. The ranges, habitat use, and dispersal, in each group availability of cover vegetation may be a particu- of lagomorphs. larly important factor in determining the eventual settlement locations of dispersing females (Avril Hares et al. 2011). Dispersal is ubiquitous and common Hares (genus Lepus; 32 species) are crepuscular/ among hares, though breeding dispersal occurs at nocturnal open-habitat specialists with long hind lower frequencies than natal dispersal. Moreover, legs which allow them to flee from potential pred- the proportion of young which disperse from the ators at high speeds. They are poorly adapted for a natal range, and the distances travelled, varies digging and rest during that day in above ground between and within species. However, movement depressions, known as forms. As they are not behavior during dispersal can give clues to navi- reliant on burrows for shelter and protection, gational capabilities. For example, dispersing lev- hares generally range over much wider areas erets have been observed to use direct long- than most rabbits and certainly all pikas (see distance exploratory movements over 1 km before “▶ Lagomorpha Life History”, Table 1). How- returning to the same resting location, over several ever, all hares and their offspring (“leverets”) days (Reid and Harrison 2010). This return behav- make use of emergent vegetation for concealment. ior suggests a capacity for accurate navigation on For example, the Irish hare (L. timidus a landscape scale. hibernicus), a subspecies of the mountain hare The locomotor activity of hares often varies (L. timidus), favors open-field habitats seasonally, with an increase in activity particularly (Dingerkus and Montgomery 2002) but is also around the start of the breeding season. During associated with rough grassland which offers this time, individuals will move from their home potential cover in the form of stands of rushes ranges in search of mating opportunities. It is (Juncus sp.; Caravaggi et al. 2015). Similarly, possible, perhaps even likely, that olfaction plays woolly hares (L. oiostolus) favor montane grass- a role in the location of mates, though olfactory lands for foraging but require intermediate shrub communication in hares is currently not a research habitats for cover (Lu 2011). Researchers study- priority. Locomotion may also be affected by per- ing movements of translocated European hares ceived predation risk (i.e., lunar illumination) and (L. europaeus) found that, rather than establishing local predator density and abundance (Rogowitz home ranges at release sites, the translocated indi- 1997); hares spend more time moving between viduals moved to find better habitats which were habitat patches, reducing stationary foraging more similar to those from which they had been time in each patch. removed (Ferretti et al. 2010). Hares will also recurrently use a network of paths between forag- Rabbits ing and/or resting sites (Caravaggi et al. 2016). There are ten genera of rabbits (Brachylagus, Dispersal, i.e., the movement of young out of Bunolagus, Capolagus, Nesolagus, Oryctolagus, the natal range (natal dispersal) or the movement Pentalagus, Poelagus, Pronolagus, Romerolagus, of adults to another breeding area (breeding dis- Sylvilagus), with a total of 29 species. Rabbits persal), is an important process with a key role in differ physically from hares in that they have Lagomorpha Navigation 3 comparatively shorter hind legs and shorter ears idahoensis) found that females dispersed up to and are physically smaller (▶ Lagomorpha Life three times further than males (Estes-Zumpf History, Table 1). Old World rabbits (all genera and Rachlow 2009). Dispersal distance may be except for Sylvilagus) are diggers, creating under- related to population density (e.g., European ground holes, burrows, and communal warrens in rabbit) (Richardson et al. 2002), with long- which to rest, avoid threats (e.g., predation, poor distance movements being more common in weather), and raise their young (known as kits or low-density populations. kittens). In contrast, new world rabbits (Sylvilagus sp.) will either utilize holes or burrows dug by Pikas other species or raise their young in aboveground There are 30 species of pika, all of which are forms. The movement behavior of rabbits is classified within a single genus, Ochotona. Pikas poorly understood, with substantial knowledge are the smallest of the lagomorphs gaps in all aspects. (▶ Lagomorpha Life History, Table 1), with Rabbits choose their home ranges with refer- rounded bodies and ears and no visible tail. ence to the vegetative composition of the land- Pikas are broadly split into two groups: (i) rock- scape, preferring areas with an abundance of or talus-dwelling species and (ii) species of grass- vegetation which could be used for cover. For land or steppe habitats. The two groups have example, researchers in Spain found that the war- different social behaviors, though they do not rens of European rabbits (O. cuniculus) were differ in life history or ecology. As with other strongly associated with the Retama mono- leporids, there is little information available on sperma, a dense flowering bush (Dellafiore et al. their movement behavior and navigational 2008). Rabbits make use of cover vegetation to capabilities. provide shelter and concealment, often using the Steppe and grassland pikas are social, living in same paths through ostensibly safe habitats to often high-density groups. In contrast, talus pikas reach foraging areas in their home ranges. are largely solitary and highly territorial. Never- European rabbits also live in underground war- theless, the dispersal behavior of the two groups is rens which may span a considerable area and have similar. For example, both breeding and natal multiple entrances. Within their home range, dispersal distances of plateau pika (O. curzoniae; therefore, European rabbits have a number of a steppe species) and American pika (O. princeps; options which offer safety from potential threats. a talus-dwelling species) are often extremely Flight to places of concealment