Hesperornis are fish-specialists that can provide useful eggs, including golden eggs for high-tier kibble, while regular eggs can be processed into oil; they can also yield organic polymer when harvested. Tamed ones are useful for hunting fish and producing eggs, though raising them takes ongoing fish access. Wild Hesperornis may aggro when approached, but their attacks are weak, so keep your distance or calmly move away rather than treating them as a serious threat. If handling or taming one, watch for nearby predators and avoid harvesting the fish you bring it.