title: Polyandry is a common event in wild populations of the Tsetse fly Glossina fuscipes fuscipes and may impact population reduction measures.
abstract: BACKGROUND
  Glossina fuscipes fuscipes is the main vector of human and animal trypanosomiasis in Africa, particularly in Uganda. Attempts to control/eradicate this species using biological methods require knowledge of its reproductive biology. An important aspect is the number of times a female mates in the wild as this influences the effective population size and may constitute a critical factor in determining the success of control methods. To date, polyandry in G.f. fuscipes has not been investigated in the laboratory or in the wild. Interest in assessing the presence of remating in Ugandan populations is driven by the fact that eradication of this species is at the planning stage in this country.
  
  
  RESULTS
  Two well established populations, Kabukanga in the West and Buvuma Island in Lake Victoria, were sampled to assess the presence and frequency of female remating. Six informative microsatellite loci were used to estimate the number of matings per female by genotyping sperm preserved in the female spermathecae. The direct count of the minimum number of males that transferred sperm to the spermathecae was compared to Maximum Likelihood and Bayesian probability estimates. The three estimates provided evidence that remating is common in the populations but the frequency is substantially different: 57% in Kabukanga and 33% in Buvuma.
  
  
  CONCLUSIONS
  The presence of remating, with females maintaining sperm from different mates, may constitute a critical factor in cases of re-infestation of cleared areas and/or of residual populations. Remating may enhance the reproductive potential of re-invading propagules in terms of their effective population size. We suggest that population age structure may influence remating frequency. Considering the seasonal demographic changes that this fly undergoes during the dry and wet seasons, control programmes based on SIT should release large numbers of sterile males, even in residual surviving target populations, in the dry season.
authors.affiliation: Department of Animal Biology, University of Pavia, Pavia, Italy.
authors.forename: Angelica
authors.initials: A
authors.lastname: Bonomi
authors.forename: Federico
authors.initials: F
authors.lastname: Bassetti
authors.forename: Paolo
authors.initials: P
authors.lastname: Gabrieli
authors.forename: Jon
authors.initials: J
authors.lastname: Beadell
authors.forename: Marco
authors.initials: M
authors.lastname: Falchetto
authors.forename: Francesca
authors.initials: F
authors.lastname: Scolari
authors.forename: Ludvik M
authors.initials: LM
authors.lastname: Gomulski
authors.forename: Eugenio
authors.initials: E
authors.lastname: Regazzini
authors.forename: Johnson O
authors.initials: JO
authors.lastname: Ouma
authors.forename: Adalgisa
authors.initials: A
authors.lastname: Caccone
authors.forename: Loyce M
authors.initials: LM
authors.lastname: Okedi
authors.forename: Geoffrey M
authors.initials: GM
authors.lastname: Attardo
authors.forename: Carmela R
authors.initials: CR
authors.lastname: Guglielmino
authors.forename: Serap
authors.initials: S
authors.lastname: Aksoy
authors.forename: Anna R
authors.initials: AR
authors.lastname: Malacrida
mesh_terms: D000818:Animals; D005260:Female; D005838:Genotype; D008297:Male; D018895:Microsatellite Repeats; D058889:Molecular Typing; D011157:Population Dynamics; D012098:Reproduction; D012621:Seasons; D012726:Sexual Behavior, Animal; D013094:Spermatozoa; D014370:Tsetse Flies / Q000254:growth & development / Q000502:physiology*; D014454:Uganda