We have already discussed the issue of ticks on rabbits where we looked at various things including their life cycle, diet, transmission, appearance, removal, treatments, control and much more.
However, since Haemaphysalis leporispalustris is the most common type ticks on pet rabbit as well as wild ones including hares and cottontails, we decided to cover on it exclusively.
Haemaphysalis leporispalustris (rabbit or grouse tick) belong to the Ixodidae characterized by a scutum (a hard shell or shield on their body) as well as a visible head that has beak-like mouth part (capitulum).
It is smaller in size, about 1/8 of an inch long and “adults are tan to reddish-tan color, with females having a slightly darker dorsal shield or scutum on the back behind the head” 
This ectoparasite affects mainly hares (Lepus ssp. including jackrabbits) and cottontail rabbits (Sylvilagus ssp.) as well as birds that feed on the ground. In cottontails and hares, you will commonly find it on the neck, ears and on the area between ears.
Finally, they are distributed through the US, Mexico, Canada, all the way to South America and they are found in tracts that are intensely managed or forest including mixed forest, deciduous and coniferous.
Their population is high during spring all the way up to summer, but it starts declining during fall.
The life cycle of Haemaphysalis leporispalustris
These arachnids’ life cycle has the egg, larvae, nymph, and adult stages. They nymph resembles adults even in color, but it is a little smaller in size and it is not fully matured with all organs in place.
A female adult rabbit tick will lay eggs when the temperature and humidity are favorable, and they will hatch into a larva which will then attach itself to mainly the birds that dwell on the ground and begin to feed on its blood.
Once fed, it will drop to the ground, molt into a nymph before getting another host, still preferably ground-dwelling birds. It feeds again and drops to the ground to molt to an adult tick.
The adult male and female rabbit ticks then find their final host, a rabbit or hare and begin feeding on its blood while they mate. Note that they can also affect other small mammals and birds.
Afterward, they again fall to the ground, the male dies while the female waits for the right time to lay eggs.
The adult H. leporispalustris are host specific and will climb vegetations that are about 12-15 centimeters to get their preferred hosts and they can sense carbon dioxide as well as sense heat of their a potential host.
Do they affect human beings?
No. Typically, they do not get attached or feed on human beings. Therefore, they rarely transmit the various disease they are a vector to including Rocky Mountain spotted fever and tularemia to people.
Furthermore, “H. leporispalustris transmits Coxiella burnetii and a Strains of Anaplasma bovis have also been found in rabbit ticks, which was discovered in a Nantucket tick study of the bacteria” 
Rabbit tick treatment and control
Although they are not a threat to human beings, they should not be left untreated since they can transmit some disease to other rodents and if their population goes very high, they may suck much blood, weaken your bunny, make it anemic (macrocytic normochromic anemia characterized by enlarged red blood cells) that can possibly kill it.
Treatment will include removal of the parasite itself which we discussed while looking at ticks on rabbits. Also, your vet may consider ivermectin which is also effective in treating fleas, mites, and worms in severe infestations.
However, insecticides such as pyrethrin, amitraz, and permethrin should not be used. Although they will kill the bunny tick they will cause secondary toxicity to bunnies.
Finally, avoid flea collars as they are harmful to bunnies, consider regularly grooming this pet especially after it has gone out to graze on your backyard, mow any long grasses and consult your vet for more preventive and control measures.