Can ticks make it through the winter?

Q. Five deer roamed my front yard this winter. Will there be ticks there this spring?

A. It’s not likely, said Thomas N. Mather, director of the Tick Encounter Resource Center at the University of Rhode Island.

The explanation has to do with the life cycle of ticks, Mather said.

There can be two types of ticks on any animal, he said, either attached and feeding or loose and wandering.

“Loose ticks would be on those deer for only a few hours, at most, before either becoming attached or falling off, and then only if it were warm enough for them to be host-seeking; that is, above freezing. Any loose ticks that might have fallen off would not likely survive on top of snow in an open front yard.

“Attached ticks stay attached and blood-feed for about seven days,” he added. “If they became engorged and then detached in your yard, they would have to survive to lay eggs; the eggs would have to hatch; the larvae would have to mature, find a host and feed, then transform into nymphs, all before you would be at much risk for a post-snow-melt tick encounter.”

For black-legged deer ticks, which transmit Lyme disease, that whole process spans two winters, Mather said. But if there are deer in your area, the process may have started a year or two ago or more, leaving the possibility of ticks in the spring.

What’s up with my body clock?

Q. Why do I wake up at exactly the same time every night, without any stimulus? It has happened all my life, and it doesn’t even matter what time I went to bed.

A. What you are experiencing is probably a normal period of relative alertness that happens in the middle of the night, said Dr. Carl Bazil, director of the division of epilepsy and sleep at New York-Presbyterian/Columbia University Medical Center.

“Most people realize that there is a natural drowsiness midday, usually around lunchtime,” he said. “This is why many fortunate cultures developed the siesta.”

But the reverse normally happens at night. The two interludes are both part of the body’s circadian rhythm, which Bazil said is “controlled by an internal clock but of course influenced by lots of external things,” like caffeine, light, exercise and stress.

Bazil said it might also help those who wake up midsleep to know that “before the advent of electrical lighting, it was normal for people to go to bed at sundown, sleep for about four hours and arise during that natural alertness for a few hours before returning for a ‘second sleep.’ ”