Gonotrophic cycle

All female vectors are assumed to find a blood meal in the first night of searching, although this fraction can be set as a model parameter. Insecticide treated nets are, for example, able to frustrate host-seeking mosquitoes [#!lemenach:07!#]. The introduction of a fraction of emerging mosquitoes would reduce the mosquito population number. It would depend on the human populationand availabilityof animals. Not only newly emerging mosquitoes seek to find a blood meal also adult mosquitoes might not be able to progress in the feeding cycle.

Once the blood meal is taken, the egg development proceeds at a rate determined by the local 2 metre air temperature $T_{2m}$, again following the degree day concept and is thus given:

$$R_{gono}=\frac{T_{2m} - T_{gono,min}}{K_{gono}}.$$ (5)

At the end of the cycle the female vector lays $N_{egg}$ eggs that will eventually hatch into females; as is usual in such models, the eggs laid that result in the males are neglected. She subsequently cycles to the meal searching box. The number of eggs is highly variable and likely depends on vector species. The choice of $N_{egg}$=80, corresponding to a batch size of 160 assuming equality between the sexes is reduced relative to [#!ermert:11b!#] but [#!lyimo:93!#,#!hogg:96!#,#!takken:98b!#] indicate that this could still be an overestimation.

Note that since version v1.6 of the model, the gonotrophic cycle is no longer explicitly bin-resolved. This is due to the fact that the fast O(2-5) day cycle was poorly resolved by the default daily timestep and resulted in numerical artifacts which were previously addressed using a stochastic term. Removing the bin-resolving scheme and resorting to a single differential equation reduces the memory requirement of the code and lead to a considerable increase in efficiency for a negligible impact on the model results.