href="@public@vhost@g@gutenberg@html@files@37595@[email protected]#Page_51" class="pginternal" tag="{http://www.w3.org/1999/xhtml}a">page 51). Conifers predominate in the forest overstory, with the following species present: jack pine (Pinus banksiana Lamb.), white pine (P. strobus L.), red pine (P. resinosa Ait.), black spruce (Picea mariana (Mill.) B.S.P.), white spruce (P. glauca (Moench) Voss), balsam fir (Abies balsamea (L.) Mill.), white cedar (Thuja occidentalis L.), and tamarack (Larix laricina (DuRoi) K. Koch). However, as a result of extensive cutting and fires much of the conifer cover is interspersed with large stands of white birch (Betula papyrifera Marsh.) and aspen (Populus tremuloides Michx.). Detailed descriptions of the forest vegetation were presented by Ohmann and Ream (1969).

Figure 1 (left half)—Map of the study area.
(Click for larger image.)

Figure 1 (right half)—Map of the study area.
BOUNDARY WATERS CANOE AREA SUPERIOR NATIONAL FOREST
(Click for larger image.)

Figure 2.—Lakes are common throughout most of the study area. (Photo courtesy of L. D. Mech.)

Figure 3.—Ridges, islands, swamps, and bays are part of the variable topography in the Superior National Forest. (Photo courtesy of L. D. Mech.)

METHODS

The observations discussed in this paper were all made from aircraft, the method of flying being that reported by Burkholder (1959) and Mech (1966a). The following aircraft were used (in order of size): Aeronca Champ,[1] Supercub, Cessna 172, Cessna 180, and Cessna 206. The smaller aircraft were excellent for holding in tight circles during observations but had the disadvantage of being slow and cold; the larger planes could cover the study area much more quickly and were more comfortable, but were not as maneuverable during observations. For radiotracking, to be discussed below, the best compromise seemed to be a Cessna 172.

To make observations of wolves, we flew over frozen waterways until tracks were found, and then followed the tracks until we lost them or saw the wolves (fig. 4). Several times we located wolves directly just by scanning the lakes. However, because there seemed to be a number of packs in the area, and because most wolves were the same color (with the exception of a few black or white individuals) (see Mech and Frenzel, page 60), it usually was not possible to follow packs from one day to the next and be certain of identification. Moreover, it was impossible to locate any pack at will because most wolves also spent much time inland.

Figure 4.—An important technique used in the study involved aerial tracking and observing of wolf packs. (Photo courtesy of L. D. Frenzel.)

Therefore, to facilitate our observations and to obtain data on wolf movements and extent of range, we began a radiotracking program in 1968-69. A professional trapper, Robert Himes, was employed to capture the wolves. Using Newhouse No. 4 and 14 steel traps at scent-post sets, he caught two wolves, and captured another with a live-snare similar to that used by Nellis (1968); the senior author trapped two additional wolves (fig. 5).

Figure 5.—A wolf caught in a trap. (Photo courtesy of D. L. Breneman.)

The four wolves held in steel traps were restrained by a choker (fig. 6), and then anesthetized by intramuscular injections (fig. 7A, B) of a combination of 30 mg. of phencyclidine hydrochloride (Sernylan, Parke-Davis Co.) and 25 mg. promazine hydrochloride (Sparine, Wyeth Laboratories) as prescribed by Seal and Erickson (1969); these drugs proved most satisfactory.

Figure 6.—A choker was used to restrain wolves caught in traps. (Photo courtesy of D. L.