December 30, 2009

On Axel again.

Since our last (Dec. 15) post of Brutus’s pack’s detailed movements, the pack covered its usual area on Ellesmere from Nov. 22 through Dec. 8. The pack visited the weather station on Dec. 8. From the station, the wolves headed north and then cut across Eureka Sound westward to Axel Heiberg Island again on Dec. 9, where they stayed for about a week. At some of the Axel locations they remained for 2 or more times, including some of the locations visited earlier. This is a pretty good indication that they killed muskoxen there. Then on Dec. 15, the pack cut back eastward across the fiord and passed by the weather station. The station staff photographed them and estimated there were 23-25 members in the pack (see photos). It is becoming ever clearer that the pack has taken advantage of the fiord’s freezing to extend its territory onto northwestern Alex Heiberg. It will be interesting now to see how many more times the wolves visit Axel and when in early summer they stop using it because of thawing.

In this second photo of Gaudet’s the wolf on the left still sports facial blood from sticking his head into a recent muskox kill.

Although not sharp, this photo from Al Gaudet, Officer in Charge of the Eureka Weather Station documents for us that on December 15 Brutus was traveling with his pack, as expected. The weather station folks estimated that the pack included 23-25 wolves on this visit.

December 22, 2009

A spaghetti map for Brutus’ movement

Brutus’ locations (small circles) since capture on 08 July 2009 to 30 November 2009. Each location is joined to the next consecutive location 12 hours apart with a line, resulting in what we call a “spaghetti” map. This joining of the dots can help us identify separate trips to a given area when there are several locations from other times. The lines joining consecutive locations are straight lines and the true path taken is likely anything but. However, it does provide us with the general direction and distance traveled. The most obvious trip we see is the one taken to Axel Heiberg Island to the west as Dave has pointed out earlier. That 129 kilometers (80 mile) trip began in the evening of 18 November and ended in the evening of 21 November, for an elapsed time of 84 hours. With the locations coming at 12-hour intervals we can’t precisely say what Brutus was doing, but no doubt he was hunting and likely resting at times too. We can also add up the distances traveled between locations and estimate a minimum distance traveled. Since monitoring began, we have received 289 of a possible 290 locations. The cumulative distance from point-to-point that Brutus has traveled up to 30 November is 2,726 km (1,683 miles). The average distance between these consecutive 12-hr locations is 9.5 km (5.8 miles) and has ranged from 0 (resting) to 41 km (25.3 miles). That 41 km distance occurred on Brutus’ trip to Axel Heiberg Island on 18 November. So far, the north-south extent of the Brutus’ locations is 93 km (57.4 miles) and the east west extent is 109 km (67.3 miles). Note that the fiords would all be frozen now and can be crossed on foot.


December 15, 2009

Brutus does Axel Heiberg!

Contrary to his other 2 visits to nearby Axel Heiberg Island just west of Ellesmere, Brutus (and no doubt his pack) actually spent much time inland on Axel rather than just along the shore.

This time, they spent at least 2 full days there, traveled at least 47 miles ( 75 km) on the island, and got as far as 11 miles (18 km) inland. Both muskoxen and arctic hares inhabit Axel, and our wolves probably partook of both. That would be the only reason to travel so far, and from the positioning of the locations we have some evidence of possible muskox kills (more about this in a later blog). Upon returning to Ellesmere, the wolves headed back to the center of their territory, and their last location was the farthest east we have ever found them, some 67 miles (107.2 km) from their farthest west location on Axel.

Remember, amount of daylight = 0; current temperature = -20 to -37 C.


December 01, 2009

Another trip to Axel Heiberg!

Picking up where we left off last time, Brutus spent much time in the southeast end of the pack’s territory and then on Nov. 14 headed about 6.5 miles (10.4 km) farther south than we had ever found him before.

He then traveled 14.1 miles westnorthwestward crossing the southeast arm of frozen Eureka Sound back to Axel Heiberg Island. 12 hours later, he was back on Ellesmere, a trek of some 8.4 miles (13.4 km), where he remained about a third of a mile (0.5 km) inland for at least the next 12 hours. Did the pack make a kill there? Of course we don’t know, but that would be one good explanation for why he (and probably the rest of his pack) spent so much time in one spot. The area is fairly flat and low, not too far from a small lake and the kind of area that muskoxen like to frequent.

Why the pack crosses to Axel Heiberg and then quickly returns to Ellesmere is still a mystery. From my work much farther south in Minnesota, I have long suspected that in autumn after the pups leave rendezvous sites and begin traveling with the adults, the parents take them around the outer extent of their territory more-or-less introducing them to all their area. Or perhaps, with the newly formed ice, the pack is just asserting itself by venturing out farther and scent-marking new areas. We’ll just have to keep watching for more data that might shed light on this question.

With temperatures reaching -37 C, we keep hoping that the collar holds up and keeps working!