PARENT SESSION
Poster Session # 20: Predator - Prey / Mutualism - Parasitism Ecology.
Thursday, August 7 Presentation from 5:00 PM to 6:30 PM. SITCC Exhibit Hall B.
Nectar-borne amino acids increase energy reserves in and reproduction by monarch butterflies.
Lanza, Janet*,1, Stephen, Marjorie1, 2, Davis, Kara1, Terry, Mylinda1, 1 University of Arkansas at Little Rock, Little Rock, AR2 Arkansas Baptist Middle School, Little Rock, AR
ABSTRACT- Nectar, the reward many plants provide for pollinators, contains water, sugar, and amino acids. Although cabbage white butterflies (Pieris rapae) and monarch butterflies (Danaus plexippus) prefer sugar-amino acid nectar mimics over sugar-only nectar mimics, the nutritional role of nectar-borne amino acids in pollinators is poorly studied. In order to determine if nectar-borne amino acids increased adult energy reserves, the number of egg-laying days, total egg production, and hatching rate, monarch butterflies were fed either sugar-only or sugar-amino acid nectar mimics of Lantana camara. Energy reserves were measured on newly emerged adult butterflies and unmated butterflies (5 day and 7 day old) fed sugar-only and sugar-amino acid nectars. Males, but not females, accumulated energy reserves more quickly when fed sugar-amino acid nectars than when fed sugar-only nectars. In order to measure the effect of amino acids on reproduction, mated females were placed in individual cages with a sprig of milkweed on which to lay eggs. Eggs were counted daily and the hatching rate was measured for twenty eggs from each butterfly each day. Compared to butterflies fed the sugar-only nectar, butterflies that were fed sugar-amino acid nectar produced more eggs and tended to lay eggs on more days. The amino acids did not affect hatching rate. These results demonstrate that nectar-borne amino acids contribute to the nutrition of monarch butterflies.
Key words: butterfly, nectar, nutrition