The Bramson logarithmic delay in the cane toads equations

Emeric Bouin (1) , Christopher Henderson (2) , Lenya Ryzhik (3)

1 CEREMADE - CEntre de REcherches en MAthématiques de la DEcision
2 Department of Mathematics [Chicago]
3 Department of Mathematics [Stanford]

We study a nonlocal reaction-diffusion-mutation equation modeling the spreading of a cane toads population structured by a phenotypical trait responsible for the spatial diffusion rate. When the trait space is bounded, the cane toads equation admits traveling wave solutions [7]. Here, we prove a Bramson type spreading result: the lag between the position of solutions with localized initial data and that of the traveling waves grows as (3/(2λ *)) log t. This result relies on a present-time Harnack inequality which allows to compare solutions of the cane toads equation to those of a Fisher-KPP type equation that is local in the trait variable.

Domaines: Equations aux dérivées partielles [math.AP]

Emeric Bouin, Christopher Henderson, Lenya Ryzhik. The Bramson logarithmic delay in the cane toads equations. 2016. ⟨hal-01379324⟩