Lineage II haplotypes detected in rats from South Africa (6 on Fig. 6A) and Java, Indonesia (111, 112 on Fig. 6A) fall outside of these clusters and are peripheral to different regions of the network. Total nucleotide divergence (Dxy; above diagonal) and net nucleotide divergences (Da; below diagonal) between the six lineages of the Rattus rattus Complex. Black rats can run at an average speed of 8 mph and can reach a maximum speed of 13 mph . They can tread on water for three days and are excellent swimmers. These animals also can climb a tree at a fast pace. The fine structure of the home range and activity pattern of free-ranging telemetered urban Norway rats, Rattus norvegicus .
Furthermore, черен плъх are invasive species, which threaten the ecology of the affected areas. This species also played a significant role in the spread of Black Death – a deadly pandemic which resulted in the deaths of over 200 million people during the 14th century. The black rat serves as prey to cats and owls in domestic settings.
Because rat ectoparasites are transmitted among individuals via close contact, this implied that rats near each other came into contact with each other more frequently than those further apart. Home range size has also been found to vary by sex, with evidence that male Norway rats occupy larger home ranges than do females (Tanaka and Kawashima, 1951; Oyedele et al., 2015). This may be due to differences in reproductive behavior, whereby males increase their ranges to actively search for mates . For example, in Norway rats, the area of the total and the core home range of males was approximately 13X and 5X larger than that of females, respectively (Oyedele et al., 2015). In black rats, the total and core home range area for males was 4X and 3.5X greater than for females, respectively (Low et al., 2013).
They can have blotches, stripes, a combination of both or be single-colored. They can be black, red, brown, yellow, gray or black-and-white colored. They have keeled scales — scales with a ridge running down the center — slender bodies and wedge-shaped heads.
In 2010, the Sociedad Ornitológica Puertorriqueña and the Ponce Yacht and Fishing Club launched a campaign to eradicate the black rat from the Isla Ratones and Isla Cardona islands off the municipality of Ponce, Puerto Rico. Rats serve as outstanding vectors for transmittance of diseases because they can carry bacteria and viruses in their systems. A number of bacterial diseases are common to rats, and these include Streptococcus pneumoniae, Corynebacterium kutsheri,Bacillus piliformis, Pasteurella pneumotropica, and Streptobacillus moniliformis, to name a few.
Stroud reported an average home range of 0.19 ha. Jackson noted an average home range radius of 50 m. The black rat is a common long-tailed rodent of the genus Rattus in the subfamily Murinae .
Sulawesi , Flores – and Timor , and in wider Melanesia –, with the earliest evidence for R. Rattus both in Timor and in Micronesia dating to around 3000 BP , –. The mtDNA data provide a clear signal of prehistoric dispersal of Black Rats into the western Pacific region during the mid- to late Holocene. The most likely source for dispersal of Lineage II rats, based on the distribution of ancestral genotypes, is Taiwan or southern China/northern Indochina.
Further, the immigration of large numbers of rats into a population may temporarily decrease the reproductive rate of the resident population . Therefore, although dispersal can maintain connectivity among populations, not all immigration events are successful, and can, in some cases, disrupt the regular population dynamics of the resident population. When temperatures drop during the winter, rat snakes enter a state of reduced metabolic activity, called brumation; the Discovery Place in Charlotte, North Carolina, explains how brumation differs from hibernation. According to Ontario Nature, gray rat snakes are the longest snakes in Canada, measuring up to 7 feet in length.