Eastern Red Spotted Newt
| |
| Kingdom: | Animalia |
|---|---|
| Phylum: | Chordata |
| Class: | Amphibia |
| Order: | Urodela |
| Family: | Salamandridae |
| Genus: | Notophthalmus |
| Species: | N. viridescens |
| Source: Integrated Taxonomic Information System | |
Eastern Red Spotted Newt
The Eastern Red Spotted Newt (Notophthalmus viridescens viridescens) is a salamander native to Eastern North America [2]. It is a common amphibian [1], which means it is cold-blooded [2] and can be found in wet forests, small lakes, streams and ponds [6]. They frequently switch between aquatic and terrestrial habitats throughout their lives. They have 4 distinct life cycles which they are able to switch between based on their environment. The stages are 1) egg, 2) aquatic larva, 3) eft (terrestrial adult) and 4) newt (aquatic adult) [2].
Description
The newt starts off as an egg. Each egg is attached to aquatic vegetation (Raritan) and a female newt can lay between 200-375 eggs per clutch. Each egg is 1.5mm in diameter [5]. After 5 weeks the larvae hatch in the water and stay there for about 3 months [1]. The larvae are olive-brown green with feathered gills. They will grow to about 7.5mm until they become efts [5]. To become efts, the larvae shed their feathered gills and adapt to life on land [1]. Efts live on the land for 3-4 years [1]. They have dry, rough skin that comes in red or bright orange colors [7]. The bright color of their skin indicates that they secrete a poisonous toxin [1]. Also indicative of their toxic secretion are the small spots placed in rows along the sides of their backs. These spots are red with black around them. They have developed this toxic secretion in order to coexist with potential predators [7]. The larger spots can be mistaken for eyes which is how their scientific name, “Notophthalmus” was given [2]. The Eft also has a round tail. In some cases, depending on the environment, the larvae can directly metamorphose into its aquatic adult form without becoming an eft [5]. Once they have become adults, the newts turn an olive green color once again, keeping the rows on red and black spots along their back, but adding black spots around the rest of their backs [2]. The male newts develop rough black patches during mating season inside their thighs and the bottom tip of their back toes [2]. As newts, they return back to the water, often being labeled as an aquatic adult. The tail of the newt is more flat than an eft and they can grow between 2.5 inches and 5.5 inches long [1].
Habitat and Range
The Eastern Red-Spotted Newt prefers to live in coniferous or damp deciduous forests [1], including vernal ponds, lakes, marshes, streams and most slow-moving, muddy waters. The eft can be found among the leaf litter in moist forest floors [2]. The ubiquitous nature of the newt opens its range all across Eastern North America, mostly east of the Mississippi river [7] and from Nova Scotia to Georgia [1].
Diet
The Eastern Red-Spotted Newt has a carnivorous [5] diet consisting of insects, fish, eggs of fish and frogs, mollusks and worms. They also eat the larvae of mosquitoes which controls their populations [1]. The larvae feed at night and can be cannibalistic [5].
Behavior & Reproduction
As Efts, they can be found from late summer into fall. They are usually seen at night but if the ground is moist enough they can be seen during the day. The adults can be found in the spring through the summer into the fall. In the winter they can be found underneath the ice to feed [2]. They can also be found under rocks and logs in the winter, hibernating [1].
The reproduction of the Newts begins with courtship [6]. Eastern newts use chemicals to attract mates [2]. The male newts wiggle their tails and use their bright spots to lure in females. The wiggling of their tail releases the chemicals. After finding a female, the male will rub his chin against her snout and hold her with his hindlegs behind her forearms [6]. Aquatic reproduction occurs in low-flow streams in forests such as pools and ponds [5].
References
[1] Creature Feature: Eastern Red-Spotted Newt - Raritan Headwaters. (n.d.). . https://www.raritanheadwaters.org/2020/03/20/creature-feature-eastern-red-spotted-newt/.
[2] Eastern (Red-Spotted) Newt - Watchable Wildlife - NYS Dept. of Environmental Conservation. (n.d.). . https://www.dec.ny.gov/animals/67022.html.
[3] ITIS - Report: Notophthalmus viridescens viridescens. (n.d.). . https://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=173616.
[4] Maryland Biodiversity Project - Eastern Newt (Notophthalmus viridescens). (n.d.). . https://www.marylandbiodiversity.com/view/470.
[5] Red-spotted Newt. (n.d.). . https://www.virginiaherpetologicalsociety.com/amphibians/salamanders/red-spotted-newt/red-spotted_newt.php.
[6] Red-Spotted Newt. (n.d.). . https://portal.ct.gov/DEEP/Wildlife/Fact-Sheets/Red-Spotted-Newt.
[7] Species Profile: Red-spotted Newt (Notophthalmus viridescens) | SREL Herpetology. (n.d.). . https://srelherp.uga.edu/salamanders/notvir.htm.
[8] The Amazing Life Cycle of the Red-spotted Newt - Credit Valley Conservation. (n.d.). . https://cvc.ca/conversations/the-transforming-life-cycle-of-a-red-spotted-newt/.