You might be underestimating how nutrient-rich a steady diet of salmon can be.
According to a ranger in Denali I spoke to:
It depends on where the bears live in relation to the food. Coastal grizzlies are much larger because they have plentiful fat and protein sources like salmon. Inland grizzlies that live near glacial streams don’t have that food source and subsist on larger quantities of berries and the like and are noticeably smaller than their coastal counterparts.
So the food sources directly impact the sizes of the animals within the same species. The grizzly I saw in Denali appeared no larger than well-fed black bears I have encountered in the Sierra Nevada range. I say appeared, because it very well may have been larger. But it certainly didn’t look like the ones near the coast.
You might be underestimating how nutrient-rich a steady diet of salmon can be.
According to a ranger in Denali I spoke to: It depends on where the bears live in relation to the food. Coastal grizzlies are much larger because they have plentiful fat and protein sources like salmon. Inland grizzlies that live near glacial streams don’t have that food source and subsist on larger quantities of berries and the like and are noticeably smaller than their coastal counterparts.
So the food sources directly impact the sizes of the animals within the same species. The grizzly I saw in Denali appeared no larger than well-fed black bears I have encountered in the Sierra Nevada range. I say appeared, because it very well may have been larger. But it certainly didn’t look like the ones near the coast.
Kind of an answer, but I’m not a bear biologist.
Salmon don’t typically run year round so it is a seasonal food source.
Coincidentally, grizzly bears don’t typically run year round, so it’s a perfect matchup.
Salmon runs are in the fall right when bears are trying to bulk up for winter hibernation.
Spring they mostly subsist on roots, grasses, and other vegetation and insects, and summer is when the berries ripen so they take advantage of that.