**9. References**

400 Modern Telemetry

juvenile to adults, utilized their environment a comprehensive study was undertaken. Round Lake was mapped using sonar technology to establish substrate types and current profiles were described at the inlet and outlet to the lake, and in the lake. The substrate map, based on roughness/smoothness and hardness/softness, were correlated with substrate

Lake sturgeons were tagged using radio and acoustic tags. Radio tags were more useful to study movements in the river due to the high flows and air bubbles in the water but were limited because of the high labour input to track individual fish. Some of the acoustic tags had both temperature and pressure sensors and the application of the VRAP acoustic system (Vemco, Canada) enabled us to obtain 3-D positioning of individual fish in real time. Results from the lake sturgeon movement studies using acoustic tags showed that there was individual variation with some fish spending most of their time on the bottom while others spent up to 75% of their time in the water column. The amount of time spent in shallow and deep water and over substrate types was determined. The movements of large (over 5 kg) and small lake sturgeon (< 2 kg) often overlapped but there was a tendency to frequent different areas i.e. smaller lake sturgeon frequented the deeper parts of the lake but were also found in shallow sections near the main flow. The most frequently used sites by both groups of lake sturgeon were near the inlet and outlet from the lake where currents were up to 1m/sec. Larger lake sturgeon moved through regions of the river where currents were up to 2m/sec. Lake sturgeon were more active over substrates consisting of fine sand, cobble,

The conventional view is that lake sturgeons are primarily a bottom feeder. However, we noted that lake sturgeon fitted with pressure sensors moved up and down the water column and spent more time in the water column than previously thought based on a review of the literature. We noted that this movement was usually correlated with emerging mayflies and postulated we were likely observing a feeding event. This led to the development of a pressure tag with the potential to record feeding events in sturgeon by measuring branchial chamber pressure. The pressure sensor consists of a cannula (PE 160) attached to the positive port, inserted under the tegument and into the parabranchial cavity under the opercular flap such that most of the cannula was not exposed to the environment. The tip of the cannula did not interfere with the movement of the gill filaments. The resolution of the sensor was 1.85 pascals digital value-1 or 0.0189 cm freshwater at 4oC. The prototype sensor was designed to be attached by wires to the receiver to obtain physiological data. The second sensor was designed to transit the signal directly to a receiver. The reason for providing this example of sensor development (feeding in this case) is that with 3-D movement studies, using a VRAP system or the more recent VPS (Vemco Ltd.), researchers are not only able to record fine scale fish movements but with new sensors like the pressure sensor can pose new questions and drive

T. Dick acknowledges financial support for these studies from a Natural Sciences and Engineering Council of Canada operating grant and from the Department of Fisheries and Oceans Canada, Environment Canada, Manitoba Hydro and Manitoba Model Forest. T. Dick also thanks elder Henry Letander, Sagkeeng First Nations, Fort Alexander, Manitoba for advice on lake sturgeon and companionship in the field. We thank Dr. M. Papst (Department of Fisheries and Oceans Canada) and Keith Kristopherson (Fisheries Branch,

types i.e. silt, fine sand, fine and coarse gravel, cobble, and rock.

technology, especially sensor technology, in new directions.

**8. Acknowledgments** 

and rock.


**19** 

*Italy* 

**Radiotracking of Pheasants** 

*Veterinary college, University of Pisa* 

**(***Phasianus colchicus* **L.): To Test** 

Marco Ferretti, Francesca Falcini, Gisella Paci and Marco Bagliacca

The common pheasant is a species that comes from Asia: its natural geographical distribution includes the central western and eastern areas of Asia, from Caucaso to Formosa island. It has been largely introduced in Europe: in Italy since Roman age, in most of central western and eastern Europe between 500 and 800 B.C.; much later it has been introduced also in North America, Hawaii islands, New Zealand and in many other countries (Cramp & Simmons, 1980; Hill & Robertson, 1988; Johnsgard, 1986). In Italy the populations of pheasant are composed of hybrids coming from subspecies of "*Phasianus colchius*" part of "*colchius*" group, "*mongolicus*" and "*torquatus*" and from the two subspecieses of "*Phasianus versicolor*" (Brichetti, 1984). At the present, the nominal subspecies can be considered extinct in Italy: the last stocks, probably extinct or genetically contaminated by captive reared pheasants released for hunting purposes, survived until the end of last century in Tuscany, Basilicata, Calabria and some other small areas of the north Italy. It is difficult to establish the consistency of the Italian population of this species, because its distribution is not known and because generally data density are missing. The Italian population is constituted by more or less isolated sub-populations, preserved in Protected Areas (PA) and in few hunting areas. The groups of animals, which are in free hunting territories, cannot be considered real populations because these groups are not selfsustaining, but they are artificially re-constituted year after year by regular restocking with new pheasants, breeders or young ones, captive reared or wild ones captured in no hunting

The breeders are selected by the farmers within the same hatching group on vivacity of temperament, origin, health, body development, size and feather condition. The weight and growing speed are so very important. The restocking, which is carried out by the farmers during January and February, is the formation of harems constituted by one male and 5-6 females, or colonies of breeders constituted by 8-10 males and 40-50 females. The breeders are raised in outside little ground pens (1 or more pheasant/sq.m) or in cages. The wild females lay approximately 15-20 eggs and the best farmed hens up to 80-100 eggs. The top of the output of the wild animals is recorded between the second and the third year of activity.

areas during the winter months (Santilli & Bagliacca, 2008).

**1.1 Rearing technique of breeders** 

**1. Introduction** 

**Captive Rearing Technologies** 

