Sensitive and Poorly-known Amphibian Species in the Santa Cruz Mountains Bioregion

California Tiger Salamander  Ambystoma californiense  (CSC, FT)
     The tiger salamander now breeds primarily in vernal (seasonal) pools and small, fishless ponds (including farm ponds). The salamanders remain upland in rodent burrows for most of the year and emerge in winter of wetter years to breed (mostly a single breeding attempt). Many populations have been eliminated by development and/or by the introduction of predatory fish to permanent ponds, resulting in either a lack of breeding or suitable upland habitat. Most existing populations are probably isolated from each other. Populations in San Benito and Monterey counties have been frequently impacted by nonnative tiger salamanders (once sold as fish bait), with which they hybridize. Within the bioregion, the remaining populations may be mostly within the Pajaro River and adjacent watersheds, although they are also present on Stanford University property.

California Tiger Salamander

California Tiger Salamander

California Giant Salamander  Dicamptodon ensatus  (CSC)

   The California giant salamander was split as a separate species from the Pacific giant salamander, with the boundary between the two in Mendocino County, and the southern boundary of the California giant salamander at the Santa Cruz County line. Both are coastal species, which reproduce in cooler, generally headwater streams, often above barriers to fish. The larvae spend 1 1/2 years in the stream, but can also sexually mature and remain in the stream and reproduce without losing their gills (paedomorphism). Terrestrial adults are usually hidden under moist cover objects or underground, and are rarely encountered except during rainy periods. Because of their cryptic habits as adults, most records are of larvae captured in streams. Little is known of their status, but they can be impacted by land-use changes and streamside logging. They can apparently be quite abundant; during a moderate first fall rain, dozens we seen peeking from bank and upslope burrows, during a nighttime eyeshine survey for red-legged frogs.

California Giant Salamander larva

California Giant Salamander larva


Santa Cruz Long-toed Salamander  Ambystoma macrodactylum croceum  (SE, FE)
     An isolated subspecies restricted to fishless or seasonal ponds between Aptos and the Elkhorn Slough watershed (especially the Ellicott Pond Preserve near Watsonville). Like the tiger salamander, adults breed after heavy rains in winter and larvae develop quickly and migrate upland by early to mid-summer. They were probably lost from many of their original habitats due to early development destroying breeding sites and by introductions of predatory fish to permanent and semi-permanent ponds. They have gradually been disappearing from the remaining documented, but isolated, breeding habitats.


Santa Cruz Long-toed Salamander. Photo by Kelli Camara

Santa Cruz Long-toed Salamander. Photo by Kelli Camara


Santa Cruz Black Salamander  Aneides flavipunctatus niger  (CSC)
The black salamander is a lungless salamander that lays its eggs in moist habitats on land in summer. They are most often found under rocks and logs in relatively moist habitats (riparian woodlands, mixed evergreen and conifer forests). They are apparently relatively scarce and are apparently declining in the bioregion, where the subspecies is endemic. Another subspecies is more common in the north coast of California.

Santa Cruz Black Salamander

Santa Cruz Black Salamander

 

Red-bellied Newt  Taricha rivularis  (CSC)
     Red-bellied newts are a medium-sized salamander (5.5 to 7.5 inches from nose to tail) with a chocolate-brown back and tomato-red underside generally found in the redwood and similar forests and streams of northern California. Their eyes are completely dark brown with no bands of bright gold as with other similar-looking Taricha species. It breeds in fast-flowing streams from March to May and spends most of the year underground. Originally, its range was described as four counties of California: Humboldt, Mendocino, Lake and Sonoma, however, a small breeding population has recently been found in Santa Clara County in the Stevens Creek watershed, 80 miles south of its main population. Researchers have been unable to determine if this isolated population is natural or introduced.

Red-bellied Newt

Red-bellied Newt

California Red-legged Frog  Rana draytonii  (FT, CSC)
     This is a large frog of lowland streams and ponds, but is now largely replaced by bullfrogs in inland and large coastal watersheds. They and the northern red-legged frog were formerly considered different subspecies of the same species. However, recent studies have separated the California red-legged frog (with breeding calls above water) from the northern red-legged frog (with breeding calls under water), which occurs from Mendocino County, north. California red-legged frogs are apparently doing well in coastal watersheds without bullfrogs. Red-legged frogs breed early in winter and are able to use seasonal habitats because of mid to late summer metamorphosis. They are usually absent from permanent ponds and streams with predatory fish and bullfrogs, but may coexist if frequent floods or pond drying depress bullfrog abundance (bullfrog tadpoles normally require 1 year to metamorphose). Red-legged frogs prefer partially shaded, low gradient streams with deep pools, steep, vegetated banks and woody debris as escape cover. They may migrate more than 1 mile to and from breeding habitats, which appear to limit the abundance of frogs in many coastal watersheds. Breeding doesn’t have to be successful every year, as the frogs can live up to ten years. Artificial (farm) ponds are potentially very valuable habitats, if fish and bullfrogs are absent.

California Red-legged Frog

California Red-legged Frog

Foothill Yellow-legged Frog  Rana boylii  (F candidate, CE)
     This is a medium-sized frog of mid-gradient, rocky, relatively open, natural streams. Yellow-legged frogs breed in late spring in streams, rather than ponds, and complete metamorphosis in late summer. They are rare in the Santa Cruz Mountains bioregion compared to red-legged frogs. West of the crest of the Santa Cruz Mountains, they are reported only from Soquel Creek, where they are common. In Santa Clara County they are more widespread in foothill streams (including Uvas and Llagas creeks upstream of their reservoirs). On-channel or off-channel ponds with bullfrogs probably result in predation that reduces yellow-legged frogs. Their mid-elevation, more open habitats are subject to substantial impacts from sedimentation, water diversion, and grazing. Flow alterations below reservoirs isolate and restrict yellow-legged frogs to (sometimes intermittent) habitats upstream of the reservoirs. They were thought to be resistant to Chytrid, an introduced fungal pathogen, although they carry the fungus. However, studies have shown reduced growth in metamorphs, and recently, localized mass mortalities of yellow-legged frogs have been reported in Upper Alameda and Coyote creeks. In July 2017 foothill yellow-legged frogs were state listed as a candidate for potential threatened or endangered status (which provided “take” protection), and in March 2020 they were listed as state endangered in the bioregion and also on the south coast (south of Monterey). Additionally they were state listed as threatened or endangered in the Sierra Nevada. Foothill yellow-legged frogs were petitioned for federal listing in July 2012, and the “90 day” finding in 2015 found that listing might be warranted. A “12 month” finding is expected in September 2020 (do the math and you can see that staff and funding limitations have produced a very slow federal listing process).

Foothill Yellow-legged Frog

Foothill Yellow-legged Frog