’Disease-smart’ assisted migration can enhance population fitness and increase resistance to pathogens via immune priming

Abstract We studied the potential of combining insect immune priming to synergize with introduction of diverse migrant to safeguard small populations from disease outbreaks that might otherwise lead to extinction. Immune priming in insects refers to the stronger immune response insects have against pathogens after prior exposure. This enhanced immunity can be passed on to offspring and holds promise for insect conservation efforts against diseases. We compared the fitness benefits to a small, inbred population of adding migrants that had not been primed to adding immune primed migrants. While both types of migrants enhanced reproduction, as in cases of genetic rescue, only primed migrants improved survival on exposure to a pathogen. Better immunity led to a trade-off with reproduction in the migrants, but not upon outcrossing with the target population, revealing synergies between hybrid vigor and immune priming. Given the demographic constraints and stochasticity that can exacerbate the effects of disease outbreaks in small populations, combining immune priming with assisted migration offers a proactive strategy to mitigate disease impacts. Competing Interest Statement The authors have declared no competing interest.