A designated or specific breeding season does not prevail in Javelina herds. Breeding occurs throughout the year but peaks during the winter months of November through March. The dominant boar does virtually all the breeding. Subordinate males do not have to leave the herd, but are not allowed to approach females in estrus. Boars and sows are capable of producing offspring at approximately 10 - 12 months of age. Wild sows, however, rarely become pregnant before 15 months. Birth occurs after an approximate 145 day gestation period. Weaning occurs at 2 to 3 months of age. An Arizona wildlife study recorded the oldest pregnant sow harvested at 12 years of age.
Numerous studies on captive and wild Javelina indicate litter size norms as single birth 41 percent, twin births 53 percent, and triplet birth a mere 6 percent. Births generally occur in bed grounds, and the piglets can travel with sow and herd a few hours after birth. Mortality rate studies indicate 25 percent at 4 months, 46 percent at 8 months, and 55 percent at 12 months-less than half make it to the first year.
Data on 1,403 hunter killed and sexed Javelina indicated a ratio of 51 percent female, 49 percent male.
At birth Javelina piglets weigh around one pound, about the size of a small cottontail rabbit. Noted Javelina expert Gerald I. Day, of the Arizona Game and Fish Department, research revealed they mature very rapidly, gaining approximately 2.8 pounds per month during the first year. At two months of age they weigh about six pounds, at four months 11 pounds, at nine months 26 pounds, and at the end of the first year, they generally weigh between 30 and 35 pounds. Their adult weight is 40 to 60 pounds. An Arizona hunter check station inspection of 168 field dressed Javelina showed the average field dressed weight as 34 pounds.
Captive Javelina enjoy a fairly long life span with the oldest recorded by the Arizona Game and Fish Department as a sow of 21 years! Texas Parks & Wildlife Department researchers recorded a wild sow at 15 years of age.
Ageing by Teeth Wear
Javelina have all their adult teeth by approximately 21 months of age. The following chart was adapted from information extracted from hunter check station data for adult Javelina (Sowls, L.K. 1961).
Young Javelina (above)
Old Javelina (7+Years)
Javelina lower jaw pictures courtesy of Amanda Moors - CouesWhitetail.com
Javelina lower jaws. Picture courtesy of Amanda Moors - CouesWhitetail.com
Note to readers. The Javelina University section was developed from information derived from over 20 different Javelina related informational sources. Please visit the References page.
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