Breeding occurs in December-February and May-June and is slightly delayed in more northern latitudes. Red Squirrels United is a three-year project supported by groups including Prince Charlesâs Red Squirrel Survival Trust, the European Squirrel Initiative and the UK Squirrel â¦ Females can mate only twice a year, but males may mate at any time. Squirrels can be killed in the breeding season too, which means that many baby animals will starve if their mothers are killed. Grey Squirrel - Sciurus carolinensis Taxon: Rodentia Grey Squirrel Red List Classification: GB: N/A England: N/A Scotland: N/A Wales: N/A Global: Least Concern General fact sheet (click to download) Habitat: Urban & gardens, deciduous woodland, mixed woodland. In late winter, squirrels may be seen courting, one, or more, chattering males chasing a female through the tree or across the ground. google_ad_slot = "9183380168"; 2006). Eastern gray squirrels have a polygynndrous (promiscuous) mating system.