When a range-shifting species colonizes an ecosystem it has not previously inhabited, it may experience suboptimal conditions that challenge its continued persistence and expansion. Some impacts may be partially mitigated by artificial habitat analogues: artificial habitats that more closely resemble a species’ historic ecosystem than the surrounding habitat. If conditions provided by such habitats increase reproductive success, they could be vital to the expansion and persistence of range-shifting species. We investigated the reproduction of the mangrove tree crab Aratus pisonii in its historic mangrove habitat, the suboptimal colonized salt marsh ecosystem, and on docks within the marsh, an artificial mangrove analogue. Crabs were assessed for offspring production and quality, as well as measures of maternal investment and egg quality. Aratus pisonii found on docks produced more eggs, more eggs per unit energy investment, and higher quality larvae than conspecifics in the surrounding salt marsh. Yet, crabs in the mangrove produced the highest quality larvae. Egg lipids suggest these different reproductive outcomes result from disparities in the quality of diet-driven maternal investments, particularly key fatty acids. This study suggests habitat analogues may increase the reproductive fitness of range-shifting species allowing more rapid expansion into, and better persistence in, colonized ecosystems.

Clutch Size Data: Clutch sizes of Aratus pisonii collected from mangrove, salt marsh, and dock habitats.

Egg Enery Data: Energy content of Aratus pisonii  eggs collected from mangrove, salt marsh, and dock habitats.

Egg Fatty Acids Data: Concentrations of fatty acids extracted from Aratus pisonii eggs collected from mangrove, salt marsh, and dock habitats.

Egg Glycogen and Gross Lipid Concentration Data: Concentrations of glycogen and gross lipids extracted from Aratus pisonii eggs collected from mangrove, salt marsh, and dock habitats.

Gonadosomatic Index Data: Relative energetic investment into reproduction, as gonadosomatic index, of Aratus pisonii collected from mangrove, salt marsh, and dock habitats.

Larval Size Data: Larval size, as dry mass at hatching, of larval Aratus pisonii hatched from eggs collected in mangrove, salt marsh, and dock habitats. Dataset includes morphological data of maternal crabs from whcih eggs were collected.

Larval Survival Data: Larval survival, as starvation resistance, of larval Aratus pisonii hatched from eggs collected in mangrove, salt marsh, and dock habitats. Dataset includes morphological data of maternal crabs from whcih eggs were collected.