The Maui News reports that, based on the latest population statistics, about 9000 humpbacks are believed to be in the North Pacific with about 60 percent spending some of their winter months in Hawaii to mate, calve, and nurse their young. We want to thank everyone for helping report the arrivals. There are a lot of spring fishermen waiting anxiously for the ice to open so they can try their luck at the 350 brown trout and 550 rainbow trout we stocked today. Males are brighter because they are the ones that display to defend a territory. Females are camouflaged to blend in with their nests.
Males are bigger for many reasons.
Their larger size makes it easier for them to survive cold weather and periods without food when they first return to northern marshes. Being larger makes them more effective at defending their territory against other redwings and predators. The males migrate as soon as marshes open up because the early bird catches the best territories. Females come later since they can't start nesting until there is reliable food for them and their babies. In Costa Rica the temperature stays pretty much the same all year round, but redwings must wait for the rainy season to breed.