Male Lek Research Articles

Do leks limit the frequency of aggressive encounters in fallow deer? Linking local male density and lek occurrence

We suggest here that the formation of leks in ungulates is a mating tactic that aims at decreasing the number of aggressive encounters in which dominant males are involved when the local male density becomes too high. Using a simulation model, we show that the spatial stability of territories in leks should limit the number of aggressive encounters between males, despite a high number of males locally present. Data on the frequencies of aggressive interactions recorded in both lekking and nonlekking fallow deer (Dama dama) populations under different local male densities support our hypothesis.

Mediterranean Fruit Fly leks: factors affecting male location

1. The mating system of Mediterranean Fruit Flies (Ceratitis capitata, Diptera: Tephritidae) is based on male leks which form within the canopies of certain trees. In this study the following hypotheses are tested: (a) fly location depends on microclimate and illumination and (b) larger and heavier males occupy preferred locations in leks. Accordingly, systematic quantitative observations of diel three‐dimensional (3‐D) locations of lekking C. capitata males were performed in field and field cage studies. 2. Fly locations were found to vary significantly during the activity hours. 3. Medflies were generally found calling from highest and most exterior locations during early morning and late afternoon hours. During the hottest hours (1200–1500) flies occupied lower locations within the tree canopy, and interior locations from 1000 to 1500. 4. Fly location (from 1000 to 1700) was correlated with the azimuth of the sun. However, the mean azimuth range of fly location was limited to 85° (59·45°–143·94°). 5. Both in the field and in the field cage the temperature, relative humidity and light intensity beneath the leaves on which the males perched were closer to the microclimate beneath fully shaded leaves than to microclimates beneath leaves exposed to direct sunlight. 6. It is concluded that male medflies occupy locations which confer suitable microclimates for calling and copulating, and suitable 3‐D locations within the canopy which provide protection from predators, wind, direct sunlight and water loss.

Do leks limit the frequency of aggressive encounters in fallow deer? Linking local male density and lek occurrence

We suggest here that the formation of leks in ungulates is a mating tactic that aims at decreasing the number of aggressive encounters in which dominant males are involved when the local male density becomes too high. Using a simulation model, we show that the spatial stability of territories in leks should limit the number of aggressive encounters between males, despite a high number of males locally present. Data on the frequencies of aggressive interactions recorded in both lekking and nonlekking fallow deer (Dama dama) populations under different local male densities support our hypothesis.

Nutritional reserves regulate male participation in Mediterranean fruit fly leks

1. The mating system of Mediterranean fruit flies (Ceratitis capitata, Diptera: Tephritidae), is based on male leks that form on the foliage of trees. Following observations that not all males participate in leks, the hypotheses that (a) small males are absent from leks and (b) males with inadequate nutrient reserves are unable to participate in leks were examined.2. The size and weight of lekking males (n = 183) and resting males captured at the same time in the vicinity of leks (n = 148) were established. In addition, using biochemical techniques, the amounts of sugar, glycogen, lipid and protein in each individual were established quantitatively.3. There was no significant size difference between lekking and resting males. However, lekking males were significantly heavier and contained significantly more sugars and protein than resting males.4. In conclusion, leks are exclusive, and only males with adequate nutritional reserves may join. Thus, in this species, reproductive success is closely linked to foraging success.

Bowers on the savanna: display courts and mate choice in a lekking widowbird

Individual display courts, constructed by lekking male Jackson's widowbirds, Euplectes jacksoni, were studied with respect to female mate choice. The court is a shaped tuft of grass, surrounded by a circular track on which displays and mating are performed. At the base of the tuft there are two cup-shaped recesses. Females sit in front of, and often pluck at, one ofthese recesses while males display at the opposite side for about 1 min before they approach and attempt to copulate. The vast majority of females visiting courts with experimentally destroyed or impaired recesses stayed shorter than the average time of male approach, whereas visits to improved courts lasted longer than visits to intact courts. All recorded copulations occurred at intact or improved courts. The display court is a weak predictor of male mating success compared to other choice cues such as display rate and tail length, but females may require the court quality to exceed a certain stimulus threshold to accept the male. Court quality correlates positively with male lek attendance and tail length. This paper discusses the implications of the results for sexual selection and considers the possibility that display courts are ‘external sexual ornaments.’ From comparative data on breeding behavior in related species, the display court and its associated behaviors are suggested to originate from male nest-initiation and female nest-inspection within an ancestral state of resource-defense polygyny.

Lek behaviour in birds: do displaying males reduce nest predation?

Male lek display in birds may reduce nest-related predation by decoying predators away from nests and alerting incubating females when a predator is approaching. The sentinel/decoy model predicts a region of decreased predator density just inside the maximum range at which predators are attracted by displaying males. The expected ring of successful nests is evident in data from three species of North American prairie grouse. Well-documented features of female mate choice in lekking species, including repeated visits to male display sites prior to mating, mate fidelity and mate copying, are consistent with females maximizing the proposed antipredator benefit. The sentinel/decoy model makes a number of unique predictions that will facilitate critical tests of the model.

Sex roles in the ghost moth Hepialus humuli (L.) and a review of mating in the Hepialidae (Lepidoptera)

Recently it has been found that female Lepidoptera belonging to diverse families actively court their males, rather than play a merely passive role. Male and female Hepialus hurnuli have bern reported to come together in three different ways: (I) females are attracted to groups or ‘leks’ of white, hovering males by visual stimuli; (2) females are attracted to the males by olfactory substances produced on the hind-tibia1 brushes of the males; (3) males are attracted to sedentary females by olfactory stimuli. During my study I observed H. humili males flying on a total of 21 nights in two different parts of England. The males hovered in groups for about 20 min each evening, starting and stopping their flights in synchrony. Timing depended on light intensity, northern moths flying later in the summer evenings than southern moths. I observed a total of 18 matings. Normally, a female from outside a male lek flew into the group and up to one of the males. This male then usually followed her to a settling position, where mating took place. In a few cases females touched males; in one case a female struck a male in the air so that both fell to the ground and were copulating when examined. Photographs of hovering males show that their hind tibia1 brushes are fully everted in flight. The organs are folded against the body when the moth is mating, at rest or dead. Whilst hovering, the males are apparently emitting pheromones which function as primary attractants, rather than as the aphrodisiacs of many other lepidopteran males. The mating behaviour of hepialids is reviewed. It is concluded that all studied hepialids which have male brush organs (some Hepialus and Oncopera, Sthenopis, zenophassus) exhibit similar flight and mating behaviour: males hover, sit or loop back and forth on the spot in leks; females fly into male aggregations and mate there (although some published observations suggest otherwise). In contrast, hepialids such as Fraus, Oxycanus and other Hepialus that lack male brush organs have mating behaviour in which the males are the active partner, a more standard lepidopteran method. In view of the controversies surrounding mating in hepialids, future systematic and behavioural work on Hepialidae throughout the world will be worthwhile.

Male Lek Formation and Female Calling in a Population of the Arctiid Moth Estigmene acrea

Abdominal coremata in male Estigmene acrea (Lepidoptera: Arctiidae) are inflated and displayed in aggregations to which females and males are attracted and where mating occurs (leks). Female E. acrea also release a sex pheromone which attracts males. These two mating behaviors occur in the same populations at different peak times on the same nights. Thus male lek formation and female calling occur in the same species, and the male coremata, or related structures, appear to be integrally associated with lek behavior.