FOOD OF AMEEICAN PHALAROPES, AVOCETS^ AND STILTS 5 
One hundred and fifty-five stomachs examined in determining the 
economic status of the northern phalarope are representative of the 
food of this bird, save when it is absent from the United States in 
winter. The material available is distributed rather evenly throughout 
the months from May to October, inclusive. That representing the 
food during the breeding season comes from Alaska, but the remainder 
was taken through the Northern States and California. Animal food 
forms 97.2 per cent, and seeds and some miscellaneous vegetable mat- 
ter make up the remainder (2.8 per cent). 
ANIMAL FOOD 
Crustacea. — In the series of stomachs examined crustaceans come 
to 9.3 per cent, and are represented in every month. Eighteen birds 
taken in September had eaten these animals to the extent of one-fourth 
of their food, but at other seasons the number taken is less. When 
phalaropes are feeding at sea, no doubt crustaceans are eaten in much 
greater quantity than here indicated. Amphipods, fragments of 
which were found in 10 stomachs, form an easily obtained food, espe- 
cially in northern waters. The curious winter eggs of another group 
of crustaceans (Daphniida?) were found in two individuals. These 
eggs resemble a small seed pod with two black spots on either side. 
They must be present in abundance in some Alaskan localities, as 
they are eaten frequently by small shorebirds. 
Brine shrimps (Artemia fertilis) were identified in eight birds taken 
on Great Salt Lake, Utah. These curious animals, less than an inch 
in length, abound in the concentrated brine of lakes in the Great 
Basin, being one of the few creatures that have become adapted to 
water so strongly saline. In Great Salt Lake these shrimps swarm 
in the shallow bays. The bodies of brine shrimps are soft and friable 
with no hard parts to resist digestion. Their detection in stomach 
examination is difficult, as the diffuse eye-spots or eggs in the case of 
breeding females, are the only characters that may be recognized. 
In the field it was observed that northern phalaropes were feeding 
extensively upon brine shrimps, and stomachs of those killed bear 
out this observation. It is certain that these crustaceans are an at- 
tractive food and that large numbers are eaten. Other crustaceans 
than those previously mentioned, in two instances isopods (Cymo- 
thoidea), were found in four other stomachs. 
Hemiptera. — True bugs are an important source of food, amounting 
to 31.8 per cent of the whole. The bulk of them are the widely dis- 
tributed water-boatmen (Corixidae), eaten by 42 birds. Back-swim- 
mers (Notonectidae) were eaten by 5 birds, and miscellaneous forms, 
mainly unidentified, by 12. The favored species in this order of 
insects are those of aquatic habit. 
Coleoptera. — Beetles were found abundantly in the examination of 
these stomachs and totaled 16.5 per cent of the food. Species that 
live in the water or are found on muddy shores are well represented. 
Ground beetles (Carabidae) were found 12 times. Crawling water- 
beetles (Haliplidae) , small species occurring in submerged vegetation, 
were taken 10 times. Four species were definitely identified. The 
predacious diving beetles (Dytiscidae) seem to be especially favored, 
adult forms being found in 20 stomachs and larval in 14. Water- 
scavenger beetles (Hydrophilidae) were found in 19- stomachs and 
their larvae in 6. Unidentified aquatic beetles occurred 14 times. 
