Rats rely on odors in their environment for information about their hierarchy among nest mates, to find food resources, find harborage, avoid predators, find mates, and navigate through their environment. Rats use scents found in urine, feces and sebum to communicate information and interact with other rats in their community. In the past, very little controlled research has been performed on how scents influence rat behaviors in their natural environment. Dr. Parsons and his research team have developed a biological assay that enables them to follow individual rats within a colony and track their movements over time, providing a window into an otherwise anonymous population of rats.

Investigators:

Michael Parsons, PhD, Fordham University, New York, New York
Rats can reproduce up to 6 times a year with litters averaging from 4 to 8 pups each.  Each night, rats can travel from 100 to 300 feet from the nest in search of food. House mice can search for food and nesting materials in an area as small as 10 feet from the nest or as far as 50 feet away.
Rats rank pretty high in terms of olfactory abilities. In fact, Harvard research shows that rats are highly sensitive to smells, and some species have even been trained to detect odors specific to land mines and tuberculosis.
Signs of Rats. … Rat droppings ↓ – Brown Rat droppings are dark brown in a tapered, spindle shape – like a grain of rice. Rub marks ↓ – Grease and dirt on their bodies leaves smudges on surfaces. Scratching noises ↓ – Black rats are agile climbers and often found in lofts to you might hear scratching noises at nightRats are larger than mice, and it’s very rare to see both occupying a home peacefully because of territory issues. Rats have also been known to hunt and consume mice when no other food sources were readily available. … If you don’t like bigger rodents,rats are worseMice and rats are very agile, not only can they jump and climb walls, they can also definitely climb into your bed as well. However, unless you have a serious mice infestation in your home, it’s unlikely that the mice in your house will climb into your bed.

Rats and Health Concerns

It is possible for rats to transmit diseases to humans. They can transmit disease if they bite or scratch humans and also by leaving their droppings and urine around the home. Humans can also get sick when rats contaminate their food or run across counter tops where food is later prepared. Some of the most common diseases transmitted to humans by rats include:
Viral infectious disease that is transmitted through the urine and saliva of rats.
Black Plague – transmitted through fleas that come from the rats and bite humans. Fleas from rats also transmit bubonic plague, typhus, and hantavirus.
Salmonellosis – if you consume food or water that has been contaminated by rat feces you can get this disease.