Home Range Studies Research Articles

A study of home range, movements and shelter use in adult and juvenile echidnas, Tachyglossus aculeatus (Monotremata: Tachyglossidae), in Western Australian wheatbelt reserves.

Ten adult and six juvenile Tachyglossus aculeatus were radio-tracked in two Western Australian wheatbelt reserves between January and November 1988. Mean body weights were 4.5 ± 0.2 kg (SE) (adults) and 2.5 ± 0.1 kg (juveniles). A maximum adult weight of 5.9 kg was recorded. Home-range determinations were based on 1848 observations (range 31 to 261 per echidna), using a modified minimum area method. Home-range sizes were 65 ± 17 ha (SE) (adults) and 23 ± 6 ha (juveniles), and these overlapped substantially. Home-range sizes and body weights were not correlated. Adults preferred low density burrows in heath at all times of year, especially in winter months. Juveniles showed no clear shelter preferences. Some shelters were used repeatedly, often with conspecifics. Shelter reuse was inversely correlated with home range size. Periodically, some T. aculeatus left reserves for different periods, using road verges and crossing long distances of farm land. These movements could not be explained by reference to mate search because they involved adults and juveniles, and occurred at varying times, sometimes well outside their known breeding period. All juveniles dispersed between August and October, at an estimated 12 months of age.

Seasonal Variations in Plasma and Tissue Chemistry in Water Snakes, Nerodia sipedon

SCHWARTZ, C. W., AND E. R. SCHWARTZ. 1974. The three-toed box turtle in central Missouri: its population, home range, and movements. Terrestrial Ser. No. 5. Missouri Depart. of Conserv., Jefferson City, Missouri. , AND A. R. KIESTER. 1984. The threetoed box turtle in central Missouri: a nineteen-year study of home range, movements and population. Terrestrial Ser. No. 12, Missouri Dept. of Conserv. SEBER, G. A. F. 1965. A note on the multiple-recapture census. Biometrika 52:249-259.

A study of home range and movements in the hedgehog (Erinaceus europaeus)

Radio‐tagged hedgehogs were studied on an area of traditionally managed farmland to obtain information about distances travelled and range areas used per night in this habitat. Data from five animals were obtained on 62 hedgehog/nights. Twelve of the data sets were eliminated owing to their incompleteness; observations of three animals (totalling 45 hedgehog/nights of acceptable data) were critically examined to establish basic procedures for future comparative studies. The concept of ‘home range’ is discussed in relation to the duration of study periods.

A review of models of home range for animal movement

Various models, both statistical and non-statistical, which have been proposed for analysing data sets collected in home range studies, are described and compared. These models may be suitable for analysing locational data obtained by such sampling methods as radio tracking or live trapping. The most useful methods for analysing home range data sets involve describing an animal's range by a probability density function of location, called the utilization distribution. Robust methods of estimation of the utilization distribution are related to the estimation of the probability function, Of this type of approach, the method of Ford and Krumme is criticised. The Harmonic Mean method of Dixon and Chapman is shown to be an improper form of the statistical method of kernel estimation. A comparison of the properties of all the models for home range considered here shows that both the Fourier Transform method proposed by D.J. Anderson and the kernel method are good because of their flexibility. The assumption of independence of locational observations which is often made is discussed and shown to be important, especially for data collected by radio tracking. Some limitations of home range studies are considered.

Lizard Home Ranges: Methodology and Functions

An evaluation of the methods for determining home ranges was made, and the factors affecting home range estimates were examined. Inadequate sample size and the use of statistically based models to correct for small sample size were the most common deficiencies in home range studies. The determinant and recapture radii methods unrealistically inflated home range estimates. The assumption of normality was not confirmed by actual data. The convex polygon method is the most attractive home range measurement to field biologists because it accurately describes the area used (if based on an adequate number of sightings), and it is simple, using only the actual sightings of an animal. By examining the relationship between number of sightings and cumulative home range size, the minimum number of sightings that accurately estimates home range can be empirically determined. Additionally, these data can provide information on the use of home ranges and territories. The time interval on which home ranges are based affect size estimates greatly. Many sightings per animal and short time intervals between censuses are necessary for accurate home range estimates. Eighteen was the minimum number of sightings to accurately measure home range size in Sceloporus virgatus. Eighteen is much larger than the minimum number commonly considered adequate. Few generalizations concerning home ranges are possible from the published data on North American iguanid lizards. The data indicate that caution is necessary in interpreting the function of home ranges from correlative data, and that the same data can support alternative hypotheses regarding function. Many researchers studying lizard populations have calculated home range size. A home range is the entire area within which an individual moves. Food, retreats, and mates are found in this area. Home range data can answer many interesting questions in ecology and behavior assuming accurate measurements of home ranges are available. In reviewing the literature on North American iguanid lizards, I found that the methodology varies so greatly between studies that the comparative value of the data is limited. Estimates of home range size for the same data vary four fold depending on the method used. This article critically evaluates the methodology commonly used in home range studies of lizards with the goal of increasing the rigorousness and reliability of home range estimates. Data from my study of Sceloporus virgatus (Rose, 1981) demonstrates the usefulness of the suggested procedures. Results from many researchers are required to make generalizations on the importance of variation in home range size, and standardized procedures are necessary to faciliate comparisons between studies. Variation in home range size is expected between species, habitats, and years. Much research is currently devoted to explain this variation. Specifically, most home range studies deal with the relationship between: 1) a lizard's social organization and its use of space; 2) home range size and function; 3) home range size, productivity of the environment, and population density; and 4) home range size, mating success, and survival.

Home Range Size in Eastern Chipmunks, Tamias striatus, as a Function of Number of Captures: Statistical Biases of Inadequate Sampling

Four summers of trapping data for the eastern chipmunk ( Tamias striatus ) were examined quantitatively in order to identify factors accounting for variation in home range size. Home range is linearly dependent upon the number of captures utilized to calculate a home range, whereas the mean percent change in home range is an asymptotic function of capture interval. In order to measure home range accurately, a minimum of twenty capture points is suggested. In analyses where home range size was based upon a minimum of four captures, significant differences were found in home range sizes between sexes, age groups and years. When strong statistical data were used in home range analysis (i.e., a minimum of 20 captures determining home range), there were no statistical differences among any categories. These results demonstrate the importance of minimum capture number in home range studies.

Analysis of Radio Telemetry Data in Studies of Home Range

In home range studies of wild animals and birds, statistical analysis of radio telemetry data poses special problems due to lack of independence of successive observations along the sample path. Assuming that such data are generated by a continuous, stationary, Gaussian process possessing the Markov property, then a multivariate Ornstein-Uhlenbeck diffusion process is necessarily the source and is proposed here to be a workable model. Its characterization is given in terms of typical descriptive properties of home range such as center of activity and confidence regions. Invariance of the model with respect to choice of an observational coordinate system is established, while data for twin deer are used to illustrate the manner in which the model may be used for study of territorial interaction. An approximate maximum likelihood procedure is proposed with results being reported for deer, coyote, and bird tracking data.

Home Range, Social Behavior, and Dominance Relationships in the African Unstriped Ground Squirrel, Xerus rutilus

A field study of home range, social behavior, and dominance relationships in the African unstriped ground squirrel, Xerus rutilus , was conducted in semi-arid bushland near Kibwezi, Kenya. Ground squirrels lived alone or in small groups in isolated burrow systems and had broadly overlapping home ranges. They were neither territorial nor colonial. Home ranges were estimated by visual observation of marked animals and those of males were considerably larger (mean = 7.01 hectares (ha); n = 4) than those of females (mean = 1.37 ha; n = 6). A continuum of agonistic behavior ranging from threat to combat is described, although actual combat was rarely observed. Sexual behavior includes a stereotyped tail display by adult males. Dominance relationships, based on 542 observed encounters between marked individuals, include a consistent male dominance over females and a fairly constant linear hierarchy among all individuals with shared home ranges. Similarities in the behavior of African ground squirrels and tree squirrels ( Sciurus ) are discussed.

A Radiotracking Study of Home Range and Activity of the Brown Lemming (Lemmus trimucronatus)

Home range was determined for brown lemmings by a radiotracking procedure throughout June and July 1972–1973 with 1795 location fixes obtained for 12 adult males, 10 adult females, and three juveniles (<20 grams) in 1972 and 3000 fixes recorded from 13 males and 12 females in 1973. Home range was calculated by the minimum area method. For 1972 animals mean male home range measured 1.33 ha (hectare) (S.D. .986, range .183 to 2.85 ha); mean female home range was .681 ha (S.D. .901, range .143 to 1.454 ha). For 1973 animals, mean male home range was .876 ha, (S.D. 1.0, range .0004 to 2.80 ha); mean female home range was .413 ha, (S.D. 1.03, range .015 to 1.68 ha). Males tended to have larger home ranges than females; 1972 home ranges tended to be larger than those of 1973 but these differences were not statistically significant. An indirect measure of activity termed change in location was defined as a difference of 2° or more in successive fixes. An analysis of this measure indicated males were significantly more active than females during both years, and 1972 animals were significantly more active than those studied in 1973. Activity was also measured directly by a telemetering system. For a sample of three males and three females, it was determined that males were active (for example, moving, feeding, and grooming) 75 percent of the time during a 24-hour period; females were active 67 percent of the time. Males spent about 69 percent of a 24-hour period outside of burrows, females 55 percent.

The Home Range of the Banded Rock Lizard Petrosaurus mearnsi (Iguanidae)

A study of the banded rock lizard (Petrosaurus mearnsi) utilizing visual observations has revealed some aspects of the home range behavior of this species. The home range of an adult male approximates 900 ft2, that of an adult female 450 ft2. The animals appear to be monogamous with the female's range being essentially contained within the male's area. The home range is entered by many transient lizards which are bobbed at and displaced by the resident males and females. This study was designed to observe the interactions and activity inside and between the home ranges of this species. The study of the home range of an animal is useful in the analysis of competition and density effects, ecological life histories, population controls, and the analysis of the social interactions of animals. The terms 'home range' and 'territory' have been defined by many authors. Most distinguish a territory as any defended area; the definition of home range on the other hand, has eluded effective definition. Many authors have defined home range as an area where an animal conducts its normal activities (Seton 1909; Burt 1943; Blair 1953; Shillito 1963; Jewel 1966). Others have defined the home range as a zone of decreasing probability of occurrence as one moves from the center of the activity. This is a statistical concept without definable boundaries (Hayne 1949; Dice and Clark 1953; Calhoun and Casby 1958; Jorgensen and Tanner 1963; Jenrick and Turner 1969). Tanaka (1963) has criticized this approach and argues that even if the size and shape may change, a home range does have boundaries. Most home range studies have used similar methods. The animals are captured, marked, released and then recaptured or sighted as many times as possible. From these data a home range is constructed with a fixed shape and size (techniques for treating the data can be found in Sanderson 1966 or Southwood 1966) with no analysis of the interactions that go on inside or between such areas. According to Turner (1971) most of

Notes on the biology of the giraffe

SummaryDuring a 3‐year study in Nairobi National Park, 1965–1968, 250 giraffe were identified by their neck markings. The herd structure of these animals was studied, including the relationships between particular individuals. Population information collected included the times of calving, the growth and longevity of giraffe, their reproductive potential, the age structure of the population and its density. Immigration, emigration and home range studies were completed with the help of radio telemetry equipment. The effect of giraffe on the vegetation and the possibility of giraffe surviving without free water are discussed.

Contribution to the knowledge of home range in common shrew Sorex araneus L.

Population density of shrews in a clearing in the submountain spruce forest was established per 1 hectare 17.5 individuals of common shrew, 4.6 of pygmy shrew and 1.1 of alpin shrew. The mean radius of activity in common shrew amounts to 13 m. The ratio of shrew to rodents was 1:3 or 1:2 in summer and autum respectively. Theoretical home range reached 532 m2. The importance of home range studies for synecological studies and theory of natural focality was demonstrated.

A Comparison of Microtus pennsylvanicus Home Ranges As Determined by Isotope and Live Trap Methods

Microtus pennsylvanicus were systematically live-trapped to gain recapture data for home range determination. Using this information, trap-revealed home ranges were plotted by several currently used methods. The same animals were then subjected to isotopic tracing. The location of each of the eight study animals was determined at approximately 45-minute intervals. These data were used to calculate isotope-revealed home ranges. Trap-revealed and isotope-revealed home ranges were then compared. This study indicates that the home ranges determined by the isotope method reflect more accurately the true situation than did those ascertained from live-trapping methods. Home ranges estimated by live-trapping methods gave a false impression of the location and actual size of the true home ranges. A study of the sequence and positions of recapture of some of the study animals indicated a shift of home range over a relatively short period of time, thus showing that time is a vital factor in the interpretation of any home range study.

A Nasal Marker for Ducks

A nasal saddle for marking ducks, of colored plasticized polyvinyl chloride tape, is described. A strip of tape was fastened to the bill with a piece of nylon threaded through the nares. The marker is easily made, durable, readily seen on ducks, and is well retained. No adverse physical or behavioral effects on 292 shovelers (Spatula clypeata) could be traced to the marker. Prior to a home-range study of the shoveler near Strathmore, Alberta, we reviewed methods of color-marking ducks. Bartonek and Dane (1964) discussed various markers and described numbered nasal discs which they considered superior to other markers. However, Erskine (cited by Bartonek and Dane 1964) had evidence that nasal discs increased merganser (Mergus sp.) mortality and believed they might be hazardous for all diving ducks. Subsequently, Bartonek (personal communication) successfully used nasal saddles heat-formed from hard plastic. The nasal saddle eliminated the projecting discs which were subject to entanglement with submersed vegetation. This paper describes a modification of Bartonek's nasal saddle. J. Bernard Gollop kindly reviewed the manuscript. MATERIALS AND METHODS Our nasal saddles were made from plasticized polyvinyl chloride tape, 13 mm wide, as used and described by Craighead and Stockstad (1956). The tape is available in 10 colors from Wildlife Supply Company, 2200 S. Hamilton Street, Saginaw, Michigan, at a cost of 12Y2 cents a yard. The one-color marker for shovelers (Fig. 1) was made from a 36-mm strip of tape. Two holes were pierced 14 mm apart with a small sharp nail or large needle (Fig. 2). Dimensions may vary slightly for other species. Washers were cut from the same kind of tape with a 7-mm rifle cartridge 984 case and were pierced. Marker and washers were fastened to the bill with 15-gauge tennis racket nylon threaded through the nares as described by Bartonek and Dane (1964). Because of its resilience, the tape binds tightly on the nylon thread without splitting. The use of a piece of nylon several inches long made the threading procedure easier. One end was prebeaded with a flame, and the other, pointed. After the marker and washers were threaded to the bill, the excess nylon was cut off and the end beaded close to the washer. Beads were checked after cooling, and redone if brittle. For a bi-colored marker, the second color was incorporated by inlaying a piece of Fig. 1. Shoveler wearing a white nasal saddle. This content downloaded from 207.46.13.127 on Wed, 12 Oct 2016 04:31:57 UTC All use subject to http://about.jstor.org/terms A NASAL MARKER FOR DUCKS * Sugden and Poston 985

An Improved Live Trap for Small Mammals

A number of live traps have been described in recent literature for the capture of small mammals. These may conveniently be classified as single and multiple-capture traps. In the single-capture traps the door is usually open in the set trap, and it is closed and locked automatically by the entering animal. This is normally accomplished by means of a treadle, false floor, or bait-tripping lever, and the door may be operated either by a spring or by gravitational force. While single-capture traps are generally effective in retaining the entering animals, they are prone to mechanical failure, and the complexity of the trapping mechanism may lead to the death of the captive animal (see Burt, 1940). This type of trap is also expensive and delicate of construction. In addition, the single-capture trap is subject to theoretical objections in population studies where the possibility of multiple captures is an important consideration, e.g., home range studies. Multiple-capture traps are so constructed that the door does not lock after the first animal enters, and hence more than one animal may theoretically be obtained at a single setting. This type of trap, while of simple construction, also has certain disadvantages. Animals frequently are able to escape, and the presence of one animal in the trap may encourage or discourage the entrance of other individuals. The trap described in the present paper is designed to eliminate certain objectionable features of the above types of traps. Essentially, the new trap is a modification of the standard wooden multiple-capture trap used by Gunderson (1950), embodying the following features. (1) The new trap is longer than usual …

Home Range of Peromyscus maniculatus rufinus in a Colorado Ponderosa Pine Community

Ecological literature of the past decade or more has indicated the value of home range information with respect to life history studies, control problems, and the estimation of small mammal populations. Nevertheless, in 1949 a review of the literature revealed little or no information of this sort available for mice in northern Colorado. This fact led to an attempt to determine the home range of several species of mice near Boulder, Colorado, during the spring and summer of 1950. The undertaking included a study of the home range of the whitefooted mouse, Peromyscus maniculatus rufinus, in an area at the northeast end of Pennsylvania Gulch, approximately one-fourth mile southwest of Sunset, Boulder County, Colorado. The results of the work in Pennsylvania Gulch are herein reported. Suggestions stemming from home range studies in other parts of the country proved helpful in organizing the present investigation. These included the work of Blair (1940, 1941, 1942) and Burt (1940, 1943) in Michigan, Hamilton (1937) in New York, and Stickel (1949) in Texas, to mention only a few. The techniques used by these people were all fundamentally the same, namely, the live-trapping, marking, releasing, and the subsequent recapture of the animals studied. The data obtained in this manner were used in a variety of ways to give home range figures. That the methods used were subject to criticism was pointed out by Mohr (1947) and Hayne (1949). The latter suggested that in the usual procedure, wherein an area was covered by a grid of live-traps in which the animals studied were captured over and over again, traps set near the home site might interfere with an animal's normal activity and reveal a home range much smaller than it actually was. The technique adopted for the present study derived from this criticism.