Ours does that too, but our bee mentor says the hives are better off in the sun, because the hive beetles don't like the heat either. Bees regulate the temperature in the hive to keep it a balmy 98 degrees all the time.
Just because the bees have found something else to forage on, does not mean that there are no polinators. Honey bees are the most visible polinators and the ones that get the most credit. They are essential for polinating a lot of the plants we grow but remember there are other kinds of bees around like the squash bees that polinate the cucurbits more than the honey bees. Wasps, flies, midges, butterflies, carpenter bees, moths, ants, bats, and beetles are a few of the others that also polinate plants.
Polinators need habitat and they like a variety of food sources not just one. Our bees really like corn tassels, basil, allyssum, sunflowers, citrus and other fruit tree blossoms, hyssop, lavender, vervain, alliums, and pretty much any small fragrant flower in bloom. In my climate I have something blooming all of the time so they stick around year round. Allysum, African basil, holy basil, and cuphea will bloom year round for me with additional flowers blooming seasonally throughout the year. I have bees visiting my garden every day. I have to actually keep disbudding the butterfly bush to keep the butterflies away. Midges polinate the cacao and butterfies and flies polinate some of the orchids. Plumeria is a thrip magnet because thrips polinate them and gardenias and desert rose are polinated by moths. To attract more of them plant a variety of their favorites and have something blooming for them so they stick around longer.
Happy gardening in Hawaii. Gardens are where people grow.