Bald-faced hornet to laying eggs while the workers take over all other necessary housekeeping tasks. At some point, sometime before the midpoint of colony life, the colony will begin to invest energy in producing reproductives as well. This marks the transition into the reproductive stage. There is an extensive time period where both workers and reproductives are raised. Production of both castes limits the size of the work force. However, an early switching time is highly adaptive for social wasp colonies in limiting the risk of total loss. In a sampling of 50 colonies taken in Maryland in 1977, workers were produced
Red-faced cormorant predators, though river otters may attempt to take them, as will corvids of various species, bald eagles and golden eagles. Gulls and corvids are common predators on eggs and chicks. Red-faced cormorant The red-faced cormorant, red-faced shag or violet shag ("Phalacrocorax urile") is a species of cormorant that is found in the far north of the Pacific Ocean and Bering Sea, from the eastern tip of Hokkaidō in Japan, via the Kuril Islands, the southern tip of the Kamchatka Peninsula and the Aleutian Islands to the Alaska Peninsula and Gulf of Alaska. The red-faced cormorant is closely related to the