Cape Lookout National Seashore's Horse Population Shows Low Birth Rate, High Mortality Rate

The horse population on Shackleford Banks stood at 109 during the past year. Kurt Repanshek photo.

Low birth rates and high mortality rates are combining to keep the growth of the horse herd at Cape Lookout National Seashore flat, according to the seashore's annual horse census.

The report, which covers the period of April 2011 through March 2012, placed the size of the herd on Shackleford Banks at 109. The population is generally managed between 110 and 130 horses, but the birth rate was lower and mortality higher than average/anticipated/expected this past year, the report said.

No contraception or removal of extra horses has occurred since 2009. This is the second year in a row that birth control has not been needed.

Six foals were born in 2011 and one was born in January of 2012. Most foals are born during the spring and summer months when nutrients are most readily available, but it is not unknown to have winter births. One 2011 foal died within a week of birth of unknown causes and another was removed at 6 months of age when his dam was unable to provide sufficient nutrients for him to survive in the wild.

Adult mortality was above average with one horse under five, five in their teens, and two in their 20s dying during this period.

Six mares tested pregnant in 2011; if they foal, they should do so before the end of June.The pregnancy tests, because of their timing, do not show mares who might foal in July or later. Summer foals are likely.