Mosquitoes need sugar more often than they need blood.

Judge as of 2022-08-16. True if entomological literature shows that adult mosquitoes (both sexes) feed on sugar such as nectar more often than females take blood meals, and that only females take blood, chiefly for egg production. Mostly true if this holds for most species but with notable exceptions (e.g. some Anopheles or Aedes populations that rarely sugar-feed). Mixed if the evidence is evenly split across major vector species. Mostly false if sugar feeding happens but generally less often than blood feeding in the major vector species, so the claim overgeneralizes. False if research shows mosquitoes generally do not need sugar or feed on it rarely.

Set before the research began.

1. E1 Frequency of Blood-feeding in Relation to Sugar Availability in Aedes aegypti and Anopheles quadrimaculatus (Diptera: Culicidae) Annals of the Entomological Society of America (Oxford Academic), authors Woodbridge A. Foster and Frank A. Eischen, Ohio State University · 1 March 1987

   “At least in part, this was due to reduced supplementary blood-feeding in honey-fed females.”

2. E2 Frequency of Blood-feeding in Relation to Sugar Availability in Aedes aegypti and Anopheles quadrimaculatus (Diptera: Culicidae) Annals of the Entomological Society of America (Oxford Academic), authors Woodbridge A. Foster and Frank A. Eischen, Ohio State University · 1 March 1987

   “Mean feeding frequency of *A. aegypti* with access to 50% honey (0.54 blood meals per female per day) was significantly lower than the frequency of those with only water (0.71 blood meals per female per day).”

3. E3 Frequency of Blood-feeding in Relation to Sugar Availability in Aedes aegypti and Anopheles quadrimaculatus (Diptera: Culicidae) Annals of the Entomological Society of America (Oxford Academic), authors Woodbridge A. Foster and Frank A. Eischen, Ohio State University · 1 March 1987

   “Mean feeding frequency of *A. quadrimaculatus* with access to honey (0.28 blood meals per female per day) was not significantly lower than the frequency of those with only water (0.31 blood meals per female per day).”

4. E4 Frequency of Blood-feeding in Relation to Sugar Availability in Aedes aegypti and Anopheles quadrimaculatus (Diptera: Culicidae) Annals of the Entomological Society of America (Oxford Academic) · 1 March 1987

   “Mean feeding frequency of *A. aegypti* with access to 50% honey (0.54 blood meals per female per day) was significantly lower than the frequency of those with only water (0.71 blood meals per female per day).”

5. E5 Frequency of Blood-feeding in Relation to Sugar Availability in Aedes aegypti and Anopheles quadrimaculatus (Diptera: Culicidae) Annals of the Entomological Society of America (Oxford Academic) · 1 March 1987

   “Mean feeding frequency of *A. quadrimaculatus* with access to honey (0.28 blood meals per female per day) was not significantly lower than the frequency of those with only water (0.31 blood meals per female per day).”

6. E6 Frequency of Blood-feeding in Relation to Sugar Availability in Aedes aegypti and Anopheles quadrimaculatus (Diptera: Culicidae) Annals of the Entomological Society of America (Oxford Academic) · 1 March 1987

   “In adult females of the mosquitoes *Aedes aegypti* (L.) and *Anopheles quadrimaculatus* Say, mean frequency of blood-feeding was measured under two ad lib. regimes: water only and 50% honey solution.”

7. E7 Natural sugar feeding rates of Anopheles mosquitoes collected by different methods in western Kenya - Scientific Reports Scientific Reports (Nature Portfolio) · 29 November 2022

   “Overall, 15.7% of collected mosquitoes had fed on natural sugar sources.”

8. E8 Natural sugar feeding rates of Anopheles mosquitoes collected by different methods in western Kenya - Scientific Reports Scientific Reports (Nature Portfolio) · 29 November 2022

   “The relatively low sugar feeding rates observed in the current study, particularly among blood-fed females, suggest wild An. gambiae s.l. and An. funestus are also able to meet their energetic needs largely through blood-feeding.”

9. E9 Sugar and blood: the nutritional priorities of the dengue vector, Aedes aegypti - Parasites & Vectors Parasites & Vectors (BioMed Central) · 21 January 2024

   “However, after the first gonotrophic cycle, they had a greater preference for blood over sugar (odds ratio, OR [95% confidence interval, CI] = 9.4 [6.7–13.0]; P < 0.001).”

10. E10 Effects of bed net use, female size, and plant abundance on the first meal choice (blood vs sugar) of the malaria mosquito Anopheles gambiae - Malaria Journal Malaria Journal (BioMed Central / Springer) · 4 January 2012

    “Evidence from the field, not just laboratory and screenhouse experiments, demonstrates unequivocally that sugar feeding is a common feature in the lives of both sexes of this species”

The evidence available as of the judging date gives no comparison of sugar-feeding frequency with blood-feeding frequency: the 1987 study (E1–E6) measured blood meals only, and E10 states that sugar feeding is common in both sexes of Anopheles gambiae. The studies suggesting blood feeding predominates (E7–E9) were published after 2022-08-16 and cover few species, so the evidence does not settle the claim under the criteria.