An Experimental Translocation of the Eastern Timber Wolf - Part 2
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Part 2

When approached by humans, all the wolves would urinate and defecate; No. 11 and 12 would pace, No. 10 (when out of the shelter box) and No.

13 would lie in the far corner of the pen and remain motionless (Fig.

14). No. 11 limped on her right front foot throughout the penned period, but this limp did not appear to have a significant effect on her activities or movements.

Blood samples taken on March 5, 1974 were a.n.a.lyzed and interpreted by Dr. U. S. Seal of the Veterans Administration Hospital in Minneapolis.

The a.s.says performed included hematology, 16 blood chemistries, thryoxine, and cortisol (Seal et al., 1975), plus estrogen and progesterone. According to Seal (personal communication), all blood values for wolves No. 10, 12, and 13 were similar and indicative of good health and minimal stress, as indicated by very low levels of the enzymes LDH, CPK, and SGOT. Such levels are typical of animals in a state of good nutrition that have been in captivity for several weeks and have accepted their captive circ.u.mstances. The MCV's were normal, indicating no vitamin deficiency, and the MCHC showed full hemoglobin content in the red cells, indicating no lack of iron. The white blood cell counts were much lower than usually seen in newly trapped wolves.

All the remaining chemistry values from these three wolves were in the normal range for the season.

[Ill.u.s.tration: _Fig. 14.--The Minnesota wolves in their Michigan pen (Photo by Tom Weise)_]

Wolf No. 11, however, differed in that she had a much higher hemoglobin level, higher blood glucose and white cell count, and higher levels of LDH, CPK, and SGOT, indicating that she was significantly stressed. This is corroborated by a low thyroxine level of 0.6 micrograms percent, which is hypothyroid for wolves.

The fibrinogen levels of all four animals were normal, indicating that there was no acute or chronic inflammation in progress.

The wolves ate well in captivity but still lost from 11% to 20% of their capture weight (Table 2). Himes estimated that they consumed an average of 8 lb. (3.6 kg) of food per wolf per day, while penned in Minnesota.

In Michigan the wolves consumed about a deer and a half, or an estimated 5.5 lb. (2.5 kg) per wolf per day. These estimates fall within the range of food consumption figures estimated for wolves in the wild (Mech and Frenzel 1971). After the wolves began feeding on the first carca.s.s, they completely consumed it before starting a second one, even though four carca.s.ses were available; they ate nothing from the other two carca.s.ses.

We released the wolves at dusk on March 12, 1974. Having just restrained Wolf No. 10 without drugs, to replace her collar, we untied her and let her free; she bounded off northwestward. We then opened the pen, and No.

12, whom we had judged to be the alpha male, left in less than 5 minutes and trotted off steadily toward the west-southwest. The remaining two animals paced around the pen for about 5 minutes and then lay down.

Because we felt that they might become too widely separated from the others, three of us approached the pen opposite the door to encourage the wolves to find the open gate. Five minutes later No. 13 left the pen running southwestward, and No. 11 left less than 5 minutes later. Upon exiting, No. 11 appeared to smell the track of No. 12 and slowly trotted in his direction.

Aerial Tracking

Our success in locating the translocated wolves by aerial radio-tracking was 95% (Table 3), similar to that of Mech and Frenzel (1971) working with wolves in their native range in Minnesota.

During the part of the study in which extensive snow cover was present (March 13 to April 20) wolves No. 11, 12, and 13 were observed 14 times from the aircraft. The first time they were seen, near Laws Lake, they appeared alarmed and moved into heavy cover. The next day, however, and on all subsequent observations, the aircraft appeared to have little effect on their behavior, although they sometimes looked up at it. No.

10 was seen only once by a pa.s.senger in the tracking aircraft, and she immediately hid from view. It seems likely that she avoided the aircraft. After the snow melted and leaves appeared, we no longer saw the wolves.

The activities of the three wolves during the 14 aerial observations were as follows: traveling 4 (Fig. 15), feeding and scavenging 5 (Fig.

16), resting 4, and sleeping 1.

_Table 3. Success in locating wolves by aerial tracking_

--------------------------------------------------------- Wolf Number 10 11 12 13 --------------------------------------------------------- Number of tracking attempts 113 65 59 67

Number of times located 105 62 59 61

Percent located 93% 95% 100% 91%

Number of times observed 1 14(Pack)

Last date tracked Nov. 17 Sept. 19 July 10 July 27 ---------------------------------------------------------

[Ill.u.s.tration: _Fig. 15.--The wolves often used woods roads for traveling (Photo by James Havemen)_]

[Ill.u.s.tration: _Fig. 16.--The released wolves were sometimes observed from the aircraft feeding on deer they had killed (Photo by Richard P.

Smith)_]

Movements of the Translocated Wolves

Wolf No. 10 never joined any of the other radioed wolves after their release, whereas the others generally remained as a pack. Thus the movements of the pack will be described separately from those of lone wolf No. 10.

Four phases were seen in the movements of the pack: (1) Post-Release Phase, March 12 to 14; (2) Directional Movement Phase, March 15 to 24; (3) Exploratory Phase, March 25 to May 7, and (4) Settled Phase, May 7 to July 6.

Post-Release Phase

This first phase of the wolves' movements, including the first 2 days after release, seemed to be characterized by confusion and indecision.

On March 13, the morning after the release, the three wolves were separated, but all remained within 2.0 miles (3.2 km) south to west of the release site, the general direction in which they had headed upon release (Fig. 17). No. 11 and 13 were about a half-mile (0.8 km) apart in the morning, and by late afternoon, No. 13 apparently had joined No.

11. No. 12 remained about 2 miles away from the others all day, although he did move about a half-mile during the day. By the 14th, No. 11 and 13 had moved 2 miles southwestward, but were separated by a half-mile; No.

12 had moved only a half-mile west.

Directional Movement Phase

During this phase, all three wolves left the immediate vicinity of the release point and headed southwestward. Early in this phase, wolves No.

11 and 13 rejoined (by March 15) and traveled 9 miles (14.5 km) west-southwest of their previous day's location, while No. 12 took a more northerly route. Nevertheless, by March 19, No. 12 had joined the other two wolves near Skanee, some 14 miles (22.5 km) west-southwest of the release point (Fig. 17). For the next several weeks these wolves all remained together and travelled a straight-line distance of about 40 miles (64.1 km) to a point just north of p.r.i.c.kett Dam about 11 miles (17.6 km) west-southwest of L'Anse, arriving there on March 24 (Fig.

17).

Exploratory Phase

In the Exploratory Phase of their movements, from March 25 to May 7, wolves No. 11, 12, and 13 covered a 1,631-square-mile (4,224 km^2) area from the town of Atlantic Mine on the Keweenaw Peninsula to the north to a point about 64 miles (103.0 km) south, near Gibbs City (Fig. 18). In the opposite dimension, they ranged from Keweenaw Bay on the east to 9 miles (14.5 km) south of Ontonagon, 42 miles (67.6 km) west of there.

This phase was characterized by long movements, considerable zigzagging, and revisiting of certain general regions such as the base of the Keweenaw Peninsula and areas east and north of Kenton (Fig. 18).

An interesting social change also occurred during this phase: No. 13 split from the pack sometime after April 26 when the pack had reached its westernmost location, south of Ontonagon. Whereas No. 11 and 12 returned east-northeastward toward Otter Lake, where they had been in late March, No. 13 headed west-northwestward to the Porcupine Mountains, 18 miles (30.0 km) west of where the pack had last been located together (Fig. 18). Thus on May 2, Wolf No. 13 was 51 miles (82.0 km) west of No.

11 and No. 12. Nevertheless, 5 days later all the wolves were found near Gibbs City, 62 miles (99.8 km) southwest of the Porcupine Mountains, and 45 miles (72.4 km) south of Otter Lake; No. 13 was only 6 miles (9.7 km) from his packmates. The next time an attempt could be made to locate the wolves, on May 16, they had reunited.

Settled Phase

This last phase of the wolves' movements includes the period when the animals had settled into an area similar to the size of home ranges reported for other wolves in the Great Lakes Region (Mech 1970). From May 7 to July 6, this pack lived in a 246-square mile (637 km^2) area with its center north of Gibbs City (Fig. 18). On July 10, wolf No. 12 was found dead. Presumably he had died by July 6, for he had not moved since then.

Wolf No. 13 had again split from his a.s.sociates between June 14 and 19 and begun to travel alone. On July 20, his remains were discovered 24 miles (38.6 km) southeast of where the pack had settled. These deaths will be discussed in detail later.

Movements of the Remaining Pack Member

After the death of her mate (No. 12), Wolf No. 11 left the 246-square-mile area in which the pack had settled (Fig. 19). By July 15, she had traveled 28 miles (45.0 km) northwest of this area and by the 20th, was back by Otter Lake, 40 miles (64.4 km) north. She returned south of Gibbs City on July 27, and was found about 3 miles (4.8 km) north of the Wisconsin border on August 2, near Lac Vieux Desert about a half mile (0.8 km) north of the Wisconsin border on August 6, and near Bruce Crossing on August 9.

[Ill.u.s.tration: _Fig. 17.--Movements during the Post-release and Directional Movement Phases of Wolves No. 11, 12, and 13_]

On August 13, Wolf No. 11 was located 1 miles (2.4 km) southeast of Ewen on the western edge of her previous locations. She was not located again until August 28. By then she had moved a straight-line distance of almost 60 miles (96.5 km) to an area in Marquette County just south of Squaw Lake, in the Witch Lake area. In doing so, she probably had pa.s.sed through the area previously explored just north of the Iron County region where the pack had spent so much of its time. These widespread movements are characteristic of lone wolves even in their native range (Mech and Frenzel 1971).

No. 11 was still in the Witch Lake area on September 2. Due to poor flying conditions we did not locate her again until September 19. At that time she was on the Floodwood Plains a quarter mile (0.4 km) north of the Floodwood Lakes. She was caught in a coyote trap during the night of September 19 and shot about 10 a.m. on September 20.

Movements of Wolf No. 10