22 SPATULA CLYPEATA 



called mud found in the stomachs. However, out of seventy stomachs analyzed by 

 McAtee of the U.S. Biological Survey, only 15 or 20% contained any ooze. The 

 stomachs were taken for the most part in November and February in the South 

 Atlantic and Gulf States. No doubt a series of summer specimens would show a 

 much higher per cent of animal food, but as it is, the animal food is over 34 %, a much 

 greater proportion than in any other American shoal-water duck except the Florida 

 Dusky Duck. Dr. E. W. Nelson, Chief of the U.S. Biological Survey, has sent me 

 unpublished notes on the result of McAtee's work from which I quote freely because, 

 although much of the diet is the same as in other ducks, there are some items of 

 great interest (see also McAtee, 1922). 



"The largest item of animal food is molluscs, practically all of them fresh -water 

 univalves. They constituted 18.97% of the total or more than half of the animal 

 food of the Shoveller. No fewer than 280 Physa heterostropha were counted in one 

 stomach contents and 1100 Amnicola floridana in another. Unidentified snails were 

 found in twenty -nine of the eighty-four stomachs examined and the following iden- 

 tified kinds in the number stated in connection with each: 



Amnicola floridana 2 Lymnaea sp. 1 



Amnicola limosa 1 Planorbis exacuous 1 



Amnicola porata 1 Planorbis parvus 4 



Amnicola sp. 2 Planorbis trivolvis 1 



Neritina reclivata 4 Physa heterostropha 2 



Physa sp. 2 



"Aquatic insects are next in importance in the regimen of the Spoonbill Duck, 

 water-bugs contributing 3.64% to the diet and water-beetles, caddis larvae, dragon- 

 fly nymphs, and all other insects together about one per cent each. The water-bugs 

 were chiefly water-boatmen (Corixidse) found in nine stomachs. These small creatures 

 swarm over the bottom ooze and play an important part in transforming nutriment 

 gathered there into meat much sought by higher forms. Other water-bugs captured 

 by the Spoonbill include back-swimmers (Notonectidae, among them Notonecta 

 undulata) , one of the medium-sized species of ' giant water-bugs ' (Zaitha) and a water 

 scorpion (Ranatra). 



"The water-beetles eaten are chiefly small species, but include a few of the highly 

 predaceous larvae known as water-tigers (Dytiscidae). A list of the water-beetles 

 identified from Shoveller stomachs is: 



Haliplus punctatus ] 



Dytiscidae 



3 



Haliplus ruficolis 



Berosus sp. 



3 



Haliplus sp. 



Tropisternus 



2 



Bidessus pullus 



Water-beetles 





Bidessus sp. 



(further unidentified) 



4 



Hydroporus sp. 







