New York State IPM Program

June 1, 2018
by Mary M. Woodsen
Comments Off on The low-down on ticks. Part 1A, Biology Q&A

The low-down on ticks. Part 1A, Biology Q&A

Ticked off about ticks? You are not alone. And knowing the what, where, why, etc. is critical to knowing how to deal with them. So here it is, the first in a series: the low-down on that pest we love to hate.

May you, dear reader, stay tick-free and healthy.

1. What, exactly, is a tick?

Ticks are related to mites and spiders—but not to insects. (Now don’t go worrying about spiders—in the Northeast, virtually all are common victims of common misunderstandings.) Ticks have four life stages: egg, larvae, nymph and adult. All stages (well, not the eggs) feed on blood for energy to grow and later to reproduce. Larval ticks have six legs; nymphs and adults have eight.

Those things that look like antenna? Not—they’re highly adapted legs that process vital information. And that snout in the middle? Blood-sucking mouthparts. (Photo CDC)

Right now, three species are a health concern here in New York: the blacklegged tick, the lone star tick, and the American dog tick.

2. What do ticks look like?

Regardless the species, unfed ticks look like flattened teardrops with eight legs. And depending on their species, life stage and sex (male versus female), they have different color patterns on their bodies. But after they’ve eaten, their abdomens (the females’ especially) can expand so much that it’s really hard to know which is which. You can get positive IDs here.

Just keep in mind that learning a tick’s identity doesn’t mean you know if it’s carrying a disease.

I wrote a sentence on my finger, period and all. And yep, the larvae are that small. (Courtesy Cal Dept Public Health)

As for size? Again, that depends on the species, its life stage, and whether it has fed (and for how long). For blacklegged and lone star ticks, larvae are the size of the period at the end of this sentence. Nymphs? Think poppy seeds. Adults? Sesame seeds. When fully fed, adult females can be as large as a raisin.

American dog ticks, though, are a tad larger than the other two.

3. Are ticks a new problem? Why have we been hearing so much more about them lately?

Turns out ticks are nothing new. In fact, evidence suggests that ticks were carrying Lyme disease pathogens 15 to 20 million years ago (Lyme Disease’s Possible Bacterial Predecessor Found in Ancient Tick). What is new? We’re seeing far more ticks throughout the Northeast and much of North America than during any time in recorded history. And of course the more ticks in the neighborhood, the greater our risk of disease.

Why are ticks on the move? For one, (sub)urban sprawl leaves small patches of wooded areas—great habitat for mice and deer but far less welcoming to their traditional enemies—hawks or foxes, cougars or wolves. (More later on the role of mice and deer in tick-borne diseases.) In addition, a warming climate makes northern areas more hospitable for ticks.

Ah, yes. A place to call home—and nary a wolf in sight. (Photo provided.)

4. Where do ticks live? How do they find me? And where did the deer ticks go?

Blacklegged ticks are usually found in woodlots, forest edges, and groundcovers such as pachysandra or periwinkle—places where leaf litter, shrubs, and tree cover provide the moist environment they need. And how do they find us? Just as we sometimes go on quests, so too do they. Only they’re not seeking adventure or the Holy Grail, but simply a host. A host that provides the food (think blood) they need to thrive, or at least survive.

About deer ticks? Years ago, researchers thought they’d found a new species and gave it the common name “deer tick.” Turned out it was the same old blacklegged tick that’s been here since time immemorial.

No matter that these ticks lack eyes—questing ticks stand on the edge of a twig or leaf, their first pair of legs extended. Evolution endowed them with cleverly designed legs: they’ve got sensors to detect temperature, the carbon dioxide those hosts exhale, and odors or sounds specific to those hosts. When a host brushes past, they grab on tight.

The nymphs typically quest below a person’s knee-height. Because adult ticks feed on larger animals, they might quest higher up to find a host—as high as your waist-height or mine.

The lone star tick is on a roll, with its own suite of diseases and syndromes — some still mysterious. (Photo CDC)

The lone star tick thrives in a wide range of habitats, from shady forests to sunny lawns or roadsides. Unlike the blacklegged tick, the lone star tick hustles toward its prey, even across pavement or dry sand. Other distinguishing features? Well … it’s lots more aggressive. Imagine a tick that travels three times as fast as the blacklegged tick, has excellent vision, and hatches in stinging swarms that can put fire ants to shame.

Last but not least—the American dog tick. Forget the woods: this tick thrives in warm, dry places—roadsides, grassy fields, scrubland and lawns. Larvae and nymphs mostly feed on small mammals, while adults climb grass, brush, or twigs to find medium-sized animals—people included. And sometimes American dog ticks could be even more aggressive. TickEncounter has reported seeing American dog ticks follow a regular source of carbon dioxide that attracted them for upward a few hundred yards to the house. And in one memorable case ticks were crawling up the outside walls toward window screens and doors. Now if that doesn’t give you the willies….

No matter which tick you might collide with—this is one party you don’t want to host.

Stay tuned for another informative post on the biology behind that pest we love to hate.

(Adapted from nysipm.cornell.edu/whats-bugging-you/ticks/tick-faqs#answers)

August 24, 2017
by Mary M. Woodsen
Comments Off on Getting ticked? Bummed about Lyme disease? You’re not alone

Getting ticked? Bummed about Lyme disease? You’re not alone

An NYS IPM Your NEWA Blog entry dropped into my inbox a couple of days ago — and since the entire conversation on my bus ride into work today was about ticks, a topic no one seemed to tire of, I just had to borrow from it for this post.

Here’s how it begins:

“Getting ticked? You’re not the only one.” That’s my colleague Dan Olmstead speaking. He continues:

“I was at Empire Farm Days working the New York State IPM Program booth last week. What do you think the most asked-about topic was?

“Every question I answered was about ticks. Ticks are most well-known as carriers of Lyme disease and they are on the rise. Changing weather and climate patterns could be partly to blame. Growing seasons are getting longer and ticks have more time to develop.”

Dan goes on to explain that range expansion is another likely factor coinciding with increasing numbers of mice and deer. These critters do well in fragmented habitat, whether it’s overgrown field, hedgerows — or expanding suburbs.

Mice infected with Lyme transmit it to the young ticks that feed on them. Meanwhile deer (birds too) pick up ticks in one place and ferry them to new, perhaps un-infested locations — making them complicit in transmitting Lyme disease despite the fact that, at least on deer, Lyme-free ticks (and yes, such ticks exist) won’t contract Lyme by feeding on deer.

But the black-legged tick (aka deer tick), host to Lyme disease and several other nasty co-infections, isn’t the only dog in the fight. It has friends — as it were. Here (courtesy the Centers for Disease Control) are the ticks we see and the most common diseases now associated with them:

Black-legged Ticks  Lyme, Anaplasmosis, Babesiosis and Powassan virus
Lone Star Ticks    Erlichiosis, STARI, and Tularemia
American Dog Ticks   Tularemia and Rocky Mountain Spotted Fever
Brown Dog Ticks Rocky Mountain Spotted Fever

When Empire Farm Days rolled around in early August, the tiny nymphs — the most dangerous stage for us humans — were still at it, still clambering onto the tall grasses and low brush or meadow plants that they’d perched on most every chance they got since May. They were waiting for the right host to come by. It’s called questing. And yes, these ticks are — metaphorically at least — on a quest that for them means life or death. (Most die but plenty remain.)

True, by now in late August, their populations have peaked. But even so they’re still eight-armed and dangerous.

Eight-armed? OK — make that eight-legged.

And typically by early August, it’s too hot and dry anyway for ticks to quest for hosts. But by early August this year, our colleague Joellen Lampman hadn’t seen the usual summer decline in black-legged tick questing. Ticks like to quest when humidity is greater than 85%, and 2017 assuredly hasn’t been stingy on that account.

Got ticks on your mind? Bummed because you’re stuck inside and feel like you can’t get out in the woods like you used to? Worried because deer have found your neighborhood, regardless how populated your neighborhood? Wondering how best to protect yourself? Seek no further: Tick Encounter is your one-stop shopping for everything you need to know. Check it out.

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