Humpback whales wintering in the entire West Indies chain are widely treated as comprising a single breeding population. However, most areas outside of Silver Bank and Samana Bay, Dominican Republic, are poorly and sporadically studied. Data is presented on the timing and movement patterns of 262 whales from the southeastern Caribbean, extending from Antigua in the north to Trinidad and Tobago in the south. Whales from the area were re-sighted in all of the major North Atlantic feeding grounds. However, of the 43 individuals re-sighted in feeding areas, animals from eastern feeding grounds were significantly over-represented, while those from western feeding areas were under-represented. This is in direct contrast to the pattern previously demonstrated in the Dominican Republic. Supporting this finding, the proportion of whales showing visible scarring on the flukes from non-lethal attack by killer whales was similar to that previously shown for Norway; yet lower than that presented from western feeding areas. The seasonal pattern of distribution in the southeastern Caribbean shows a peak of occurrence about six weeks later than in the Dominican Republic, and there is little overlap in the periods of greatest use. Sightings are uncommon before February. The peak in abundance occurs during March and April, declining during May, with some sightings extending into June. This is consistent with the pattern of sightings from historical whaling records in the southeastern Caribbean. These results suggest that the humpbacks mating and calving in this region are not a representative subset of those that winter in the Dominican Republic. Further studies will be needed to examine the spatial nature of the pattern shown here and define the nature and limits of this group, but these results suggest that some part of this breeding area represents a previously un-described distinct population segment within the North Atlantic. Given this, the widely held idea that there is a single West Indies humpback whale distinct population segment is in need of reconsideration.

No abstract

The treatment of the reinvestment rate assumption in the literature is sufficiently ambiguous that many. conclude that reinvestment is included in the mechanics of calculating internal rate of return and net present value while others assume that reinvestment is only an implicit assumption necessary when two or more alternatives are compared [7). B ecause of this confusion, many students experience difficulty in grasping the basic concepts of capital analysis. The purpose of this paper is to help clear up this confusion by answering the question: Is a reinvestment rate assumed in the mechanics of calculating the internal rate of return? The Problem To highlight the issue, consider the following investment opportunity in which an initial outlay of $2,880 is made at time t = 0, and cash inflows of $2,000 occur at the end of each of the next two years.

Identification photographs of humpback whales taken in the eastern Caribbean were compared with photographs from the North Atlantic to identify re-sightings. Nine individuals were identified in the eastern Caribbean region, seven of these in the Grenadine Islands. There were three re-sightings. Two individuals were re-sighted in northern feeding grounds: one between Newfoundland and Saba Bank; the other between Greenland and Grenada. This demonstrates movement between this breeding and calving area and two of the primary humpback whale feeding grounds in the North Atlantic. The re-sighting rate (0.222) is comparable to the rate of re-sightings between feeding grounds and other breeding areas in the North Atlantic. Another individual was re-sighted in Puerto Rico and Dominica, demonstrating an exchange between the eastern Caribbean and another breeding and calving area in the West Indies.

No abstract