Search

Radiotelemetry is used to quantify behavioral, ecological, and physiological variables of animals. Because of technological limitations, relative transmitter size generally increases with decreasing body mass of the study animal, and the recommended transmitter mass of Key words: internal transmitters, maximum running speed, Planigale gilesi, Sminthopsis crassicaudata

A joint analysis of tag return and telemetry data should improve estimates of mortality rates for exploited fishes; however, the combined approach has thus far only been tested in terrestrial systems. We tagged subadult red drum (Sciaenops ocellatus) with conventional tags and ultrasonic transmitters over 3 years in coastal North Carolina, USA, to test the efficacy of the combined telemetry--tag return approach. There was a strong seasonal pattern to monthly fishing mortality rate (F) estimates from both conventional and telemetry tags; highest F values occurred in fall months and lowest levels occurred during winter. Although monthly F values were similar in pattern and magnitude between conventional tagging and telemetry, information on F in the combined model came primarily from conventional tags. The estimated natural mortality rate (M) in the combined model was low (estimated annual rate [+ or -] standard error: 0.04 [+ or -] 0.04) and was based primarily upon the telemetry approach. Using high-reward tagging, we estimated different tag reporting rates for state agency and university tagging programs. The combined telemetry--tag return approach can be an effective approach for estimating F and M as long as several key assumptions of the model are met. Une analyse combinee du retour des etiquettes et des donnees de telemetrie devrait ameliorer les estimations des taux de mortalite des poissons exploites; cependant, une telle approche conjointe n'a a ce jour ete testee que dans les systemes terrestres. Nous avons marque des tambours rouges, Sciaenops ocellatus, avec des etiquettes ordinaires et des emetteurs a ultrasons sur une periode de trois annees sur la cote de la Caroline du Nord, E .-U., pour evaluer l'efficacite de l'utilisation combinee du retour des etiquettes et de la telemetrie. Il existe un fort patron saisonnier dans les estimations du taux mensuel de mortalite due a la peche (F) faites a partir des etiquettes ordinaires et celles de telemetrie; les valeurs maximales de F s'observent a l'automne et les plus faibles en hiver. Bien que les patrons et l'importance des valeurs mensuelles de F soient semblables a partir du marquage classique et de la telemetrie, l'information sur F dans le modele combine provient surtout des etiquettes ordinaires. Le taux estime de mortalite naturelle (M) dans le modele combine est faible (taux annuel estime [+ or -] erreur type : 0,04 [+ or -] 0,04) et il se base principalement sur les donnees de telemetrie. En utilisant un programme de marquage avec de fortes recompenses, nous avons estime des taux de retour des etiquettes differents pour les programmes menes par l'organisme de l'etat et par l'universite. L'approche qui combine le retour des etiquettes et la telemetrie peut etre efficace pour estimer F et M a la condition que plusieurs des presuppositions principales du modele soient respectees. [Traduit par la Redaction], Introduction Obtaining accurate estimates of the fishing and natural mortality rates experienced by fish stocks is a central goal of fisheries stock assessment. Regulation of the fishing mortality rate (F) [...]

The effects of habitat on the ecology, movements, and foraging strategies of marine apex predators are largely unknown. We used acoustic telemetry to quantify the movement patterns of blacktip reef sharks (Carcharhinus melanopterus) at Palmyra Atoll National Wildlife Refuge, in the Pacific Ocean. Sharks had relatively small home ranges over a timescale of days to weeks (0.55 [+ or -] 0.24 [km.sup.2]) and showed strong site fidelity to sand-flat ledges within the west lagoon over a three-year period. Sharks showed evidence of diel and tidal movements, and they utilized certain regions of the west lagoon disproportionately. There were ontogenetic shifts in habitat selection, with smaller sharks showing greater selection for sand-flat habitats, and pups (total length 35-61 cm) utilizing very shallow waters on sand-flats, potentially as nursery areas. Adult sharks selected ledge habitats and had lower rates of movement when over sand-flats and ledges than they did over lagoon waters. Fractal analysis of movements showed that over periods of days, sharks used patches that were 3-17% of the scale of their home range. Repeat horizontal movements along ledge habitats consisted of relatively straight movements, which theoretical models consider the most efficient search strategy when forage patches may be spatially and temporally unpredictable. Although sharks moved using a direct walk while in patches, they appeared to move randomly between patches. Microhabitat quantity and quality had large effects on blacktip reef shark movements, which have consequences for the life-history characteristics of the species and potentially the spatial distribution of behaviorally mediated effects on lower trophic levels throughout the Palmyra ecosystem. Key words: acoustic telemetry; blacktip reef sharks; foraging behavior; fractal analysis; habitat utilization; nursery areas; Palmyra Atoll; predator-dominated ecosystems.

The manner in which space is utilized by animals is influenced by several factors, including habitat quality and the distribution and abundance of resources. We used 4 years (2000-2003) of radiotelemetry data to investigate the space-use pattern of female Florida black bears (Ursus americanus floridanus) in the Ocala National Forest and an adjacent residential community of Lynne, north-central Florida. Annual home-range size (95% fixed kernel density estimator) ranged from 3.8 [km.sup.2] to 126.9 [km.sup.2], and averaged ([+ or -] SE) 24.2 [+ or -] 3.55 [km.sup.2]. Home ranges were largest during 2000 when a drought led to a forest-wide mast failure, suggesting that abundance of food resources can substantially influence space-use pattern. Home-range sizes during autumn (19.92 [+ or -] 4.59 [km.sup.2]) were substantially larger than during summer (8.26 [+ or -] 0.99 [km.sup.2]). Although annual home-range size did not differ between the 2 study sites, home ranges in summer were smaller in Lynne (5.30 [+ or -] 1.01 [km.sup.2]) than in Ocala National Forest (9.82 [+ or -] 1.29 [km.sup.2]), whereas home ranges in autumn were twice as large in Lynne (35.76 [+ or -] 13.91 [km.sup.2]) as in Ocala National Forest (13.24 [+ or -] 1.80 [km.sup.2]). We suggest that site-specific differences in the size of seasonal home range are due to differences in habitat characteristics and the degree of habitat fragmentation between the 2 study sites. Key words: Florida black bear, home range, kernel density method, minimum convex polygon, space use, Ursus americanus floridanus

An acoustic telemetry system for remotely monitoring and recording a variety of sounds generated by desert mule deer held in an outdoor enclosure using a digital camcorder and commercial wireless microphone and receiver components is developed. The system provided a simple, relatively inexpensive but powerful means of monitoring detailed foraging behaviors of ungulates.

Biotelemetry was employed in monitoring body temperature and spontaneous locomotor activity in rats to evaluate adjuvant arthritis time-course. The development of arthritic index, cartilage protoglycan synthesis, indomethacin effects and circulating levels of inflammation-promoting cytokines were also examined. Results verify indomethacin's systemic and symptomatic inhibitory effects on cartilage metabolism, locomotor activity and fever.

The fisher, a member of the same family as weasels and wolverines, is in danger of losing its habitat. Once ranging from Canada's British Columbia to the Pacific Northwest, in the 1990s it is found on either side of the Canada-United States border and in some parts of California's Sequoia National Forest. Biotelemetry studies show the fisher prefers to live in the trunks of old oaks and conifers. Its diet includes small mammals, fish and porcupines. Maintaining a healthy population of fishers could require a long legal battle.

Biotelemetry, through radio transmitters glued to the top of spotted turtles' shells, has helped biologists monitor the movement, hibernation locations, feeding sites and other behaviors. They tend to be creatures of habit, following similar routes and searching for food where they have fed before. Field observations have shown spotted turtles can live for 20 or 30 years in the wild.

Satellite telemetry of Wandering Albatrosses (Diomedea exulans) breeding on the Crozet Islands, southwestern Indian Ocean, revealed two distinct foraging strategies during successive stages of the breeding season: systematic foraging over extensive distances; and use of specific areas close to the colony. During early incubation, Wandering Albatrosses foraged over pelagic waters at an average range of 1,284 km. The length of the foraging trips decreased towards the end of the incubation period. During the first month of chick rearing when parents brood alternately for short periods, the foraging range, distance covered, and area prospected were further reduced. Males tended to return to an individual foraging area, located at the edge of the continental shelf, that had previously been visited during the long trips of the incubation period. Females mostly prospected pelagic waters just off the shelf. After the chick had been left alone on the nest, birds exhibited a two-fold strategy, combining long foraging trips over pelagic waters with short trips over the shelf. Generally, both sexes headed for and foraged over an extensive pelagic sector. Some males also foraged over the Kerguelen shelf. Females tended to forage over more northerly waters than males. The duration of the foraging trips was most closely related to the total distance covered, but also to the maximum range during the long trips of the chick-rearing period and to a lesser extent during the incubation period. There were no such significant relationships in the case of short trips. During long pelagic foraging trips, the birds had a looping course that was determined by the wind direction, suggesting random foraging with respect to prey distribution. We were able to show that Wandering Albatrosses use two foraging strategies to cope with the constraints imposed by the different stages of the breeding cycle, the availability of prey, and the distribution of the prey. Use by Wandering Albatrosses of two foraging strategies may be a compromise based on the simultaneous need to satisfy the different food requirements of chicks and parents.

Multiplex acoustic transmitters are attached to six blue marlin (Makaira nigricans) to monitor the depth, swimming speeds, body temperature and water temperature preference. Results show that the blue marlin spend over 50 percent of the time within 10 meter of the surface. Moreover, they prefer to remain in 22 to 27 degrees (Celsius) surface waters and spend most of their time above the thermocline in the 26 to 27 degrees (Celsius) mixed layer which is 70 to 100 meters deep during the summer months. Lastly, muscle temperature was similar to water temperature.

A three-channel biotelemetry system has been designed and implemented for use in a chronically instrumented animal model of cardiovascular disease. A dual-channel ultrasonic transit-time micrometer allows monitoring of left-ventricular wall motion for the regions perfused by the left circumflex and left anterior descending coronary arteries. A third channel provides left ventricular blood pressure obtained from a high-fidelity blood pressure transducer implanted in the left ventricle. The biotelemetry system features a high voltage dc-dc converter for improved ultrasonic signal strength, a time-to-voltage converter that is highly immune to synchronization frequency variations, low power consumption (approx. 100 mW), small size (4 x 6 x 12 cm), and low weight (approx. 200 g). This three-channel system has enabled our laboratory to continuously monitor untethered animals for 24-h periods. Data obtained from this miniature biotelemetry system can be utilized to quantify myocardial oxygen demand and regional left-ventricular wall thickening.

The home-range models are subjected to correction for the location of mule deer and the results with uncorrected models were found to be biased low by 18.4% and high by 19.2% compared to corrected estimates.

Habitat use by ruffed grouse during the brood-rearing period is assessed by comparing characteristics of tree, shrub, and ground layers at ruffed grouse brood, and random locations in forests of Quebec, Canada. Females with broods are found to use specific mixed and regenerated clearcut stands, and grouse locations are found to have higher lateral obstruction, higher small-stem density and are closer to roads and trails than random locations.

M.P. HEIDE-JORGENSEN [1,2] N. HAMMEKEN [1] R. DIETZ [3] J. ORR [4] P.R. RICHARD [4] (Received 21 January 2000; accepted in revised form 28 November 2000) ABSTRACT. Time spent at [...]

P.R. RICHARD [1] A.R. MARTIN [2] J.R. ORR [1] (Received 18 November 1999; accepted in revised form 30 May 2000) ABSTRACT. Beluga whales of the eastern Beaufort Sea stock were [...]

A.R. MARTIN [1] P. HALL [2] P.R. RICHARD [2] (Received 11 April 2000; accepted in revised form 23 October 2000) ABSTRACT. Beluga diving was studied in western Hudson Bay, where [...]

JACK R. ORR [1] RICKY JOE [2] DAVIDEE EVIC [3] (Received 18 November 1999; accepted in revised form 24 October 2000) ABSTRACT. For many decades, humans have captured white whales [...]

R. DIETZ [1,2] M.P. HEIDE-JORGENSEN [3] P.R. RICHARD [4] M. ACQUARONE [1] (Received 1 February 2000; accepted in revised form 2 November 2000) ABSTRACT. Ten narwhals (Monodon monoceros) were instrumented [...]

MICHAEL C.S. KINGSLE [1,2] SERGE GOSSELIN [1,3] GRY A. SLENO [1,4] (Received 18 November 1999; accepted in revised form 16 November 2000) INTRODUCTION ABSTRACT. Three adult and three juvenile belugas [...]

P.R. RICHARD [1] M.P. HEIDE-JORGENSEN [2] J.R. ORR [1] R. DIETZ [3] T.G. SMITH [4] (Received 18 November 1999; accepted in revised form 25 January 2001) ABSTRACT. Twenty-one adult belugas [...]

ROBERT S. SUYDAM [1] LLOYD F. LOWRY [2] KATHY J. FROST [2] GREG M. O'CORRY-CROWE [3] DANNY PIKOK Jr. [4] (Received 25 November 1999; accepted in revised form 10 February [...]

100-channel neurostimulation circuit comprising a complementary metal oxide semiconductor (CMOS), application-specific integrated circuit (ASIC) has been designed, constructed and tested. The ASIC forms a significant milestone and an integral component of a 100-electrode neurostimulation system being developed by the authors. The system comprises an externally worn transmitter and a body implantable stimulator. The purpose of the system is to communicate both data and power across tissue via radio-frequency (RF) telemetry such that externally programmable, constant current, charge balanced, biphasic stimuli may be delivered to neural tissue at 100 unique sites. An intrinsic reverse telemetry feature of the ASIC has been designed such that information pertaining to the device function, reconstruction of the stimulation voltage waveform, and the measurement of impedance may be obtained through noninvasive means. To compensate for the paucity of data pertaining to the stimulation thresholds necessary in evoking a physiological response, the ASIC has been designed with scaleable current output. The ASIC has been designed primarily as a treatment of degenerative disorders of the retina whereby the 100 channels are to be utilized in the delivery of a pattern of stimuli of varying intensity and or duty cycle to the surviving neural tissue of the retina. However, it is conceivable that other fields of neurostimulation such as cochlear prosthetics and functional electronic stimulation may benefit from the employment of the system. Index Terms--Neurostimulator, retina, telemetry, vision prosthesis, VLSI.

The estimation of survival distributions for radio-tagged animals is important to wildlife ecologists. Allowance must be made for animals being lost (or censored) due to radio failure, radio loss, or emigration of the animal from the study area. The Kaplan-Meier procedure (Kaplan and Meier 1958), widely used in medical studies to censoring, can be applied to this problem. We developed a simple modification of the Kaplan-Meier procedure that allows for new animals to be added after the study begun. We present 2 examples using telemetry data collected from nothern bobwhite quail (Colinus virginianus) to show the simplicity and utility of the Kaplan-Meier procedure and its modifications. The log rank test used to compare 2 survival distributions can also be modified to allow for additions during the study. Simple computer programs that can be run on a personal computer are available from the authors.