The response of fall webworm larvae, Hyphantria cunea, to identical feeding stimuli presented in a series of multiple choice tests was studied in the laboratory. Instead of responding independently, all larvae in 61 % of the trials were observed to aggregate at one of two identical feeding stations

Cannon, William N, Jr.

English

ValpoScholar

The Great Lakes Entomologist 
Volume 18 
Number 2 - Summer 1985 Number 2 - Summer 
1985 
Article 3 
June 1985 
Social Feeding Behavior of Hyphantria Cunea Larvae 
(Lepidoptera: Arctiidae) in Multiple Choice Experiments 
William N. Cannon Jr. 
USDA Forest Service 
Follow this and additional works at: https://scholar.valpo.edu/tgle 
 Part of the Entomology Commons 
Recommended Citation 
Cannon, William N. Jr. 1985. "Social Feeding Behavior of Hyphantria Cunea Larvae (Lepidoptera: 
Arctiidae) in Multiple Choice Experiments," The Great Lakes Entomologist, vol 18 (2) 
Available at: https://scholar.valpo.edu/tgle/vol18/iss2/3 
This Peer-Review Article is brought to you for free and open access by the Department of Biology at ValpoScholar. 
It has been accepted for inclusion in The Great Lakes Entomologist by an authorized administrator of ValpoScholar. 
For more information, please contact a ValpoScholar staff member at scholar@valpo.edu. 
SOCIAL FEEDING BEHAVIOR OF HYPHANTRIA CUNEA LARVAE 
(LEPIDOPTERA: ARCTIIDAE) IN MULTIPLE CHOICE 
EXPERIMENTS 
William N. Cannon, Jr.] 
ABSTRACT 
The response of fall webworm larvae, Hyphantria cunea, to identical feeding stimuli 
presented in a series of multiple choice tests was studied in the laboratory. Instead of 
responding independently, all larvae in 61 % of the trials were observed to aggregate at one 
of 
two identical feeding stations. 
In studies 
to determine the food preferences of insects and to creen insect attractants, 
arrestants, and feeding stimulants, we often have to decide whether to work with 
individual insects or with groups of insects. 
The larvae of the fall webworm, Hyphantria cunea (Drury), are naturally gregarious. 
They build nests of silk in which groups of them feed together. However, earlier 
laboratory studies had shown that larvae of the "black race" (Oliver 1964) that were 
confined in 100 x 20-mrn petri dishes, did not show a pronounced tendency to aggregate. 
Perhaps gregariousness was manifested only in the larger area encompassed by the nest. 
This suggested a hypothesis, that larvae confined in such small areas act independently 
in feeding. To test this hypothesis we experimented with multiple choice tests to determine 
whether fall webworm larvae would act independently in feeding. 
MATERIALS AND METHODS 
The larvae were reared in the laboratory on the artificial diet described by Yearian et 
al. (1966). Newly ecdysed third-ins tar larvae were chosen at random for the feeding tests. 
The larvae had been fed on the artificial diet since hatching but had been starved for about 
8 h before the tests. 
Two plugs of the artificial diet were placed in 100 x 20-mrn disposable petri dishes, at 
opposite edges (designated posts A and B; Fig. 1). Four larvae were released at the center 
of 
each 
of the 72 dishes in the experiment. After 24 h in a rearing chamber, the dishes were 
examined and the number of larvae at each diet plug was recorded. 
Because the same diet was used at each post, the probability of a larva feeding at post 
A was assumed to be the same as that of feding at post B. It was assumed that each larva 
would select a diet post independently of the others and that no larva would refuse to feed. 
The binomial probabilities of the four outcomes of each trial were determined, and the 
theoretically expected frequencies were compared with the observed frequencJes by the 
chi-square goodness-of-fit test (Sokal and Rohlf 1969). 
iNortheastem Forest Experiment Station, USDA Forest Service, Delaware, OH 43015 
1
Cannon: Social Feeding Behavior of Hyphantria Cunea Larvae (Lepidoptera:
Published by ValpoScholar, 1985
80 THE GREAT LAKES ENTOMOLOGIST Vol. 18, No.2 
Fig. 1. Test arena used in food preference experiments. 
Table 1. Distribution of fall webworm larvae at plugs of the same diet medium in a 
feeding preference experiment. 
Distribution of larvae (72 dishes) 
Number of larvae 
Post A Post B 
Expected 
frequencies 
Observed 
frequencies 
o 
1 
2 
3 
4 
4 
3 
2 
1 
o 
4.5 
18.0 
27.0 
18.0 
4.5 
24 
9 
8 
11 
20 
RESULTS AND DISCUSSION 
The results show that the tendency of individual fall web worm larvae to feed on a 
particular plug was greatly influenced by other members of the group. In 44 of the 72 tests, 
all four larvae in the dish were found at one post (Table 1). In 20 tests, three larvae were 
at one post and one larva at the other post. Computed chi-square values showed a 
significant departure from expected frequencies (X2 158.5, P < 0.001). The hypothesis 
that each larva would act independently in feeding was rejected. 
It 
would appear that third-instar larvae retain their gregariousness under laboratory 
conditions. This colonial habit 
of the fall webworm appears to play an important role when 
newly hatched larvae are becoming established on host leaves. Groups of larvae have a 
higher rate of survival than an isolated larva (Watanabe and Umeya 1968). It is possible 
2
The Great Lakes Entomologist, Vol. 18, No. 2 [1985], Art. 3
https://scholar.valpo.edu/tgle/vol18/iss2/3
1985 THE GREAT LAKES ENTOMOLOGIST 81 
that feeding by a larva attracts others to the feeding site, forming the beginnings of the
colonial nest. This type of group feeding behavior has been reported for the jack pine 
sawfly, Neodiprion pratti banksianae Rohwer (Ghent 1960). Sawfly larval feeding groups 
were found to build up around a solitary larva that had begun to feed by itself. Additional 
larvae then joined the feeding site. 
The results of this study and those of other researchers indicate that if the design of an 
experiment requires more than one insect to be used in a test arena, the hypothesis that the 
insects will react independently should be tested thoroughly. 
LITERATURE CITED 
Ghent, A. W. 1960. A study of the group-feeding behaviour of larvae of the jack pine 
sawfly, Neodiprion pratti banksianae Roh. Behaviour 16:110-148. 
Oliver, A. D. 1964. A behavioral study of two races of the fall webworm, Hyphantria 
cunea, in Louisiana. Ann. Entomol. Soc. Amer. 57:192-194. 
Sokall, R. R. and F. J. Rohlf. 1969. Biometry, the principles and practice of statistics in 
biological research. Freeman and Co., San Francisco. 776 p. 
Watanabe, N. and K. Umeya. 1968. Biology f Hyphantria cunea Drury (Lepidoptera: 
Arctiidae) in Japan. IV. Effects of group size on survival and growth of larvae. Japanese 
Plant Prot. Servo Res. Bull. 6:1-6. 
Yearian, W. C., K. L. Gilbert, and L. O. Warren. 1966. Rearing the fall webworm, 
Hyphantria cunea (Drury) (Lepidoptera: Arctiidae) on a wheat germ medium. J. Kansas 
Entomol. Soc. 39:495-499. 
3
Cannon: Social Feeding Behavior of Hyphantria Cunea Larvae (Lepidoptera:
Published by ValpoScholar, 1985


Social Feeding Behavior of Hyphantria Cunea Larvae (Lepidoptera: Arctiidae) in Multiple Choice Experiments

Valparaiso University

The Great Lakes Entomologist Volume 18 Number 2 - Summer 1985 Number 2 - Summer 1985 Article 3 June 1985 Social Feeding Behavior of Hyphantria Cunea Larvae (Lepidoptera: Arctiidae) in Multiple Choice Experiments William N. Cannon Jr. USDA Forest Service Follow this and additional works at: https://scholar.valpo.edu/tgle  Part of the Entomology Commons Recommended Citation Cannon, William N. Jr. 1985. "Social Feeding Behavior of Hyphantria Cunea Larvae (Lepidoptera: Arctiidae) in Multiple Choice Experiments," The Great Lakes Entomologist, vol 18 (2) Available at: https://scholar.valpo.edu/tgle/vol18/iss2/3 This Peer-Review Article is brought to you for free and open access by the Department of Biology at ValpoScholar. It has been accepted for inclusion in The Great Lakes Entomologist by an authorized administrator of ValpoScholar. For more information, please contact a ValpoScholar staff member at scholar@valpo.edu. SOCIAL FEEDING BEHAVIOR OF HYPHANTRIA CUNEA LARVAE (LEPIDOPTERA: ARCTIIDAE) IN MULTIPLE CHOICE EXPERIMENTS William N. Cannon, Jr.] ABSTRACT The response of fall webworm larvae, Hyphantria cunea, to identical feeding stimuli presented in a series of multiple choice tests was studied in the laboratory. Instead of responding independently, all larvae in 61 % of the trials were observed to aggregate at one of two identical feeding stations. In studies to determine the food preferences of insects and to creen insect attractants, arrestants, and feeding stimulants, we often have to decide whether to work with individual insects or with groups of insects. The larvae of the fall webworm, Hyphantria cunea (Drury), are naturally gregarious. They build nests of silk in which groups of them feed together. However, earlier laboratory studies had shown that larvae of the "black race" (Oliver 1964) that were confined in 100 x 20-mrn petri dishes, did not show a pronounced tendency to aggregate. Perhaps gregariousness was manifested only in the larger area encompassed by the nest. This suggested a hypothesis, that larvae confined in such small areas act independently in feeding. To test this hypothesis we experimented with multiple choice tests to determine whether fall webworm larvae would act independently in feeding. MATERIALS AND METHODS The larvae were reared in the laboratory on the artificial diet described by Yearian et al. (1966). Newly ecdysed third-ins tar larvae were chosen at random for the feeding tests. The larvae had been fed on the artificial diet since hatching but had been starved for about 8 h before the tests. Two plugs of the artificial diet were placed in 100 x 20-mrn disposable petri dishes, at opposite edges (designated posts A and B; Fig. 1). Four larvae were released at the center of each of the 72 dishes in the experiment. After 24 h in a rearing chamber, the dishes were examined and the number of larvae at each diet plug was recorded. Because the same diet was used at each post, the probability of a larva feeding at post A was assumed to be the same as that of feding at post B. It was assumed that each larva would select a diet post independently of the others and that no larva would refuse to feed. The binomial probabilities of the four outcomes of each trial were determined, and the theoretically expected frequencies were compared with the observed frequencJes by the chi-square goodness-of-fit test (Sokal and Rohlf 1969). iNortheastem Forest Experiment Station, USDA Forest Service, Delaware, OH 43015 1Cannon: Social Feeding Behavior of Hyphantria Cunea Larvae (Lepidoptera:Published by ValpoScholar, 198580 THE GREAT LAKES ENTOMOLOGIST Vol. 18, No.2 Fig. 1. Test arena used in food preference experiments. Table 1. Distribution of fall webworm larvae at plugs of the same diet medium in a feeding preference experiment. Distribution of larvae (72 dishes) Number of larvae Post A Post B Expected frequencies Observed frequencies o 1 2 3 4 4 3 2 1 o 4.5 18.0 27.0 18.0 4.5 24 9 8 11 20 RESULTS AND DISCUSSION The results show that the tendency of individual fall web worm larvae to feed on a particular plug was greatly influenced by other members of the group. In 44 of the 72 tests, all four larvae in the dish were found at one post (Table 1). In 20 tests, three larvae were at one post and one larva at the other post. Computed chi-square values showed a significant departure from expected frequencies (X2 158.5, P < 0.001). The hypothesis that each larva would act independently in feeding was rejected. It would appear that third-instar larvae retain their gregariousness under laboratory conditions. This colonial habit of the fall webworm appears to play an important role when newly hatched larvae are becoming established on host leaves. Groups of larvae have a higher rate of survival than an isolated larva (Watanabe and Umeya 1968). It is possible 2The Great Lakes Entomologist, Vol. 18, No. 2 [1985], Art. 3https://scholar.valpo.edu/tgle/vol18/iss2/31985 THE GREAT LAKES ENTOMOLOGIST 81 that feeding by a larva attracts others to the feeding site, forming the beginnings of thecolonial nest. This type of group feeding behavior has been reported for the jack pine sawfly, Neodiprion pratti banksianae Rohwer (Ghent 1960). Sawfly larval feeding groups were found to build up around a solitary larva that had begun to feed by itself. Additional larvae then joined the feeding site. The results of this study and those of other researchers indicate that if the design of an experiment requires more than one insect to be used in a test arena, the hypothesis that the insects will react independently should be tested thoroughly. LITERATURE CITED Ghent, A. W. 1960. A study of the group-feeding behaviour of larvae of the jack pine sawfly, Neodiprion pratti banksianae Roh. Behaviour 16:110-148. Oliver, A. D. 1964. A behavioral study of two races of the fall webworm, Hyphantria cunea, in Louisiana. Ann. Entomol. Soc. Amer. 57:192-194. Sokall, R. R. and F. J. Rohlf. 1969. Biometry, the principles and practice of statistics in biological research. Freeman and Co., San Francisco. 776 p. Watanabe, N. and K. Umeya. 1968. Biology f Hyphantria cunea Drury (Lepidoptera: Arctiidae) in Japan. IV. Effects of group size on survival and growth of larvae. Japanese Plant Prot. Servo Res. Bull. 6:1-6. Yearian, W. C., K. L. Gilbert, and L. O. Warren. 1966. Rearing the fall webworm, Hyphantria cunea (Drury) (Lepidoptera: Arctiidae) on a wheat germ medium. J. Kansas Entomol. Soc. 39:495-499. 3Cannon: Social Feeding Behavior of Hyphantria Cunea Larvae (Lepidoptera:Published by ValpoScholar, 1985

https://scholar.valpo.edu/cgi/viewcontent.cgi?article=1530&context=tgle

Social Feeding Behavior of Hyphantria Cunea Larvae (Lepidoptera: Arctiidae) in Multiple Choice Experiments

Abstract

Similar works

Full text

Available Versions

ValpoScholar

Valparaiso University