The length of pregnancy, or gestation, in deer varies slightly depending on the species, but it generally ranges from 200 to 220 days. Here’s a breakdown of the gestation periods for common deer species:

1. White-Tailed Deer

• Gestation Period: Approximately 200 to 205 days (about 6.5 to 7 months).
• Mating Season: Typically occurs during the fall, often in November, with the fawns being born in the spring, around May to June.

2. Mule Deer

• Gestation Period: Around 200 to 210 days (about 6.5 to 7 months).
• Mating Season: Mule deer mate during the fall, with births occurring in late spring to early summer.

3. Black-Tailed Deer

• Gestation Period: Similar to mule deer, around 200 to 210 days.
• Mating Season: These deer mate in the fall and give birth in spring.

4. Elk

• Gestation Period: About 240 to 250 days (approximately 8 months).
• Mating Season: Elk typically mate in the fall, with calves being born in late spring to early summer.

5. Red Deer

• Gestation Period: Similar to elk, around 230 to 240 days (about 7.5 to 8 months).
• Mating Season: Red deer also mate in the fall and give birth in spring.

6. Fawn Birth and Care

Deer typically give birth to one or two fawns at a time, although triplets are possible in some cases. The fawn is usually born with its eyes open and is able to stand and walk shortly after birth. The mother will often leave the fawn hidden in tall grass or brush to avoid predators, only returning to nurse it periodically.

Conclusion

• Most Deer Species: The average pregnancy duration for most deer species, like white-tailed and mule deer, is about 200 to 210 days (around 6.5 to 7 months).
• Elk and Red Deer: These larger species have a longer gestation period of about 230 to 250 days (roughly 7.5 to 8 months).

Fawns are typically born in the spring, after the mating season in fall, which aligns with when food resources are most abundant and environmental conditions are favorable for the newborns.