The Behavior of Noddy and Sooty Tenis. 229 



government tug to Key West. There food was purchased for them (min- 

 nows). At 3 a. m., Friday the 14th, Dr. Jordan boarded the Mallory boat 

 Denver, which left at that time for New York. On board the boat the birds 

 were both watered and fed. On Sunday, the i6th. at 9'^ 20" a. m., the 

 birds were released at lat. 35 8', long. 75 10' (12 miles east of Cape Hat- 

 teras approximately). The wind was fair and fresh for several days after 

 the birds were released. I kept their nests under constant observation, but 

 had almost given up hope of their returning when, to my surprise, on June 

 21, at 8" 30'" a. m., I found both marked sooties on their respective nests. 



None of the marked noddies was ever found at its old nest, but several 

 days after the sooties had been observed at their nests, by chance I ob- 

 served one of my marked noddies attempting to alight on its nest. On 

 account of the mate having formed new " affiliations " this was not per- 

 mitted, and I immediately lost track of the bird.^ I have little doubt that 

 the other no<ldies also returned to the island, but likewise were not permitted 

 to return to their nests. 



The distance from Hatteras to Bird Key in a straight line is approxi- 

 mately 1367.9 km. (850 statute miles). The alongshore route, which is the 

 one in all probability chosen by the birds on their return, since they were 

 gone several nights, is approximately 1739.6 km. (1,081 statute miles). - 



Experiment III. 



On Monday, Jul}' 8. two noddies and two sooties were captured and 

 marked and given into the charge of Dr. Hartmeyer, who was returning to 

 Germany by way of Havana. The birds were in such poor condition, 

 owing to the enormous strain of several da}s' feeding of their then quite 

 large young, that we decided to release them at Havana instead of taking 

 them farther out. On the 9th the birds were carried by Dr. Hartmever 

 on board the Government tug and taken to Key West, where they spent the 

 night and part of the following day, the loth. They were carried in Dr. 

 Hartmeyer's stateroom to Havana on the night of the loth. Early in the 

 morning of the nth the birds were released in Havana Harbor. All re- 

 turned to Bird Key on the 12th. Since they had had to spend three days 

 without food or water, they were in poor physical condition. They prob- 

 ably spent one day and night around the shores of Cuba, leaving there early 



' At one of the sooty nests the egg had hatched. The egg at the other nest had 

 hatched before the bird was captured. Apparently the 2 sooties wiiich were left at 

 the nests cared for the young birds without aid from the outside, the young being 

 simply left in the nest while the parent sought the food. The behavior of the noddies 

 left at home presents an interesting contrast to the " faithfulness " of the sooties. 

 .^fter 3 days had passed, one of the noddies took a new mate. At the other 2 nests 

 one of the most peculiar incidents of my stay was happening. These two nests were 

 in the same bush, one about 6 inches above the other. Both the birds remained stolidly 

 on their nests for 48 hours without going for food ; they then began leaving the nest 

 regularly for food and water, brooding the egg and feeding at intervals closely 

 approximating the normal. Finally the bird in the upper nest began bringing food 

 to the bird in the nest below. Each time on bringing the food, the bird from the 

 upper nest would nod and bill and coo to the bird below reactions wholly similar to 

 those engaged in by newly mated pairs. The eggs in both nests were neglected, no 

 effort being made to keep them constantly covered. Sometimes the bird from the 

 upper nest would spend a half hour or more in the lower nest. Sometimes the bird 

 in the lower nest would spend its time in the upper nest. Again at times both birds 

 would be away from the nests simultaneously. 



"It might be well to mention that the birds were transported in the hold of the 

 Denver. 



