Answer
No. Population growth rate would probably be affected more by mean generation time since that determines how long it takes to reproduce. However, there could be extreme cases where the opposite is true (for example, no reproduction for 40 years and then 10,000 babies at once).
Work Step by Step
It is hard to say, from the information given, a sure answer, but generation time would seem more critical. Fig. 55.26 shows that the species with the longest mean generation time are those, if you check elsewhere in the book, with the smallest populations on the chart.