Spea hammondii

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Spea hammondii
Spea hammondii 1.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Amphibia
Order: Anura
Family: Scaphiopodidae
Genus: Spea
Species:
S. hammondii
Binomial name
Spea hammondii
(Baird, 1859)
Synonyms [2]
  • Scaphiopus hammondii Baird, 1859 "1857"
  • Spea hammondiiCope, 1866

Spea hammondii, also known as the western spadefoot, western spadefoot toad, Hammond's spadefoot, [2] or Hammond's spadefoot toad, [3] is a species of amphibian in the family Scaphiopodidae. [2] It is found in western California (USA) and northwestern Baja California (Mexico). The specific name hammondii is in honor of physician and naturalist William Alexander Hammond. [3]

Contents

Description

Spea hammondii is a relatively smooth-skinned species of American spadefoot toad. Its eyes are pale gold with vertical pupils. It has a green or grey dorsum, often with skin tubercles tipped in orange, and has a whitish color on the abdomen. On each hind foot is a wedge-shaped black spade. Adult toads are between 3.8 and 7.5 cm (1.5 and 3.0 in) long. Juveniles have a similar appearance to adults, but with more distinct spotting.

Distribution

Populations of Spea hammondii are localized, but widespread. It ranges throughout the central valley of California and as far south as San Diego and some parts of the desert. The western spadefoot prefers grassland, scrub and chaparral locally but can occur in oak woodlands. It is nocturnal, and activity is limited to the wet season, summer storms, or during evenings with elevated substrate moisture levels. It is easily handled, with less skin secretions than similar toad species. Their secretions smell like peanut butter and may cause sneezing. [4] The western spadefoot is experiencing some habitat loss, but is still common in its range and the population declines are very minor even though it is listed as "near threatened" in some counties of CA.

Diet

Tadpoles feed mainly on plants and planktonic organisms, algae, ants, small invertebrates and dead aquatic larvae of amphibians, they may become cannibalistic. Adult toads feed on insects, worms and other invertebrates including; grasshoppers, true bugs, moths, ground beetles, ladybird beetles, click beetles, spiders, flies, ants and earthworms.

Life span and reproduction

The average life span for Spea hammondii is about 12 years. They reach sexual maturity in their third year. The female spadefoot toad will lay up to 2,000 eggs per season. The cordon of eggs attaches to objects in the water or puddles or ditches and the male deposits sperm on them. Tadpoles emerge in as little as 15 hours. After hatching, the tadpole's only chance for survival is to develop into a toad before the puddle dries up, which takes 12 to 13 days. This is the fastest metamorphosis known for any frog or toad. Reproduction: the breeding of laying eggs normally occur from late winter to the end of March. Males will be heard during this period. Females lay numerous small, irregular clusters that will contain from 10 up to 42 eggs. They may lay more than 500 eggs in one season. Egg to transformation may occur in 8–16 days.

Conservation

Southern California

Spea hammondii has lost up to 80% of its native habitat due to urban development within Southern California. Most of the remaining vernal pools that the toads rely on for reproduction lie on protected public land or preserves. [5] Spadefoot toads have been known to take advantage of man-made standing water sources such as road ruts, cattle ponds, and artificial pools. The species is currently under review to be listed on the federal Endangered Species Act. However, it is listed as a Species of Interest for the Central Subarea and a fully covered species for the Coastal Subarea on the Natural Community Conservation Plan (NCCP) and Habitat Conservation Plan (HCP) for the County of Orange Central and Coastal Subregion. Within this region, Spea hammondii is managed as though it is listed as a state and federal endangered species. [5]

Development in Orange County placed populations of Spea hammondii under threat, and they were relocated to newly constructed mitigation pools in 2005 and 2006. These mitigation pools are located in East Orange, Shoestring Canyon, and Irvine Mesa within Orange County Parks in the foothills of the Santa Ana mountains. A study was conducted in 2016 to monitor the reproductive success of the toads at these mitigation pools. It found that none of the five pools at East Orange or the six at Shoestring Canyon retained water during the 2016 rainy season. 12 of the 16 pools at Irvine Mesa retained water for more than 30 days. Of these 12, seven pools had successful reproduction with newly metamorphosed frogs. [6] A 1991 study found that the average duration of vernal pools that produced metamorphosed frogs was 83.1 days. [7] The soil at the East Orange and Shoestring Canyon sites was believed to be too porous to hold water, and the study recommended that soil may need to be compacted underneath the mitigation pools. Another suggestion was use an artificial lining under the pools to hold water. Overall, it was concluded that the mitigation pools were successful with a surviving population of Spea hammondii after 10 years. [6]

A restoration project began in 2019 with a partnership between the California Department of Fish and Wildlife, California State Parks, Orange County Parks, and the Natural Communities Coalition to create 16 artificial breeding pools across Crystal Cove State Park and Laguna Coast Wilderness Park. [8] The pools are expected to be completed in 2023. [8] Ten pools will be lined with clay, while the other six will be lined with PVC to study differences in water retention. [9] The project also will restore 15 acres of coastal sage scrub around the pools to provide foraging areas for the spadefoot toads, as well as nesting opportunities for the cactus wren. [9]

Related Research Articles

<span class="mw-page-title-main">Frog</span> Order of amphibians

A frog is any member of a diverse and largely carnivorous group of short-bodied, tailless amphibians composing the order Anura. The oldest fossil "proto-frog" Triadobatrachus is known from the Early Triassic of Madagascar, but molecular clock dating suggests their split from other amphibians may extend further back to the Permian, 265 million years ago. Frogs are widely distributed, ranging from the tropics to subarctic regions, but the greatest concentration of species diversity is in tropical rainforest. Frogs account for around 88% of extant amphibian species. They are also one of the five most diverse vertebrate orders. Warty frog species tend to be called toads, but the distinction between frogs and toads is informal, not from taxonomy or evolutionary history.

<span class="mw-page-title-main">Tadpole</span> Larval stage in the life cycle of an amphibian

A tadpole is the larval stage in the biological life cycle of an amphibian. Most tadpoles are fully aquatic, though some species of amphibians have tadpoles that are terrestrial. Tadpoles have some fish-like features that may not be found in adult amphibians such as a lateral line, gills and swimming tails. As they undergo metamorphosis, they start to develop functional lungs for breathing air, and the diet of tadpoles changes drastically.

<span class="mw-page-title-main">Vernal pool</span> Seasonal pools of water that provide habitat

Vernal pools, also called vernal ponds or ephemeral pools, are seasonal pools of water that provide habitat for distinctive plants and animals. They are considered to be a distinctive type of wetland usually devoid of fish, and thus allow the safe development of natal amphibian and insect species unable to withstand competition or predation by fish. Certain tropical fish lineages have however adapted to this habitat specifically.

<span class="mw-page-title-main">European spadefoot toad</span> Family of amphibians

The European spadefoot toads are a family of frogs, the Pelobatidae, with only one extant genus Pelobates, containing six species. They are native to Europe, the Mediterranean, northwestern Africa, and western Asia.

<span class="mw-page-title-main">American spadefoot toad</span> Family of amphibians

The Scaphiopodidae are a family of American spadefoot toads, which are native to North America. The family is small, comprising only seven different species.

<i>Scaphiopus</i> Genus of amphibians

Scaphiopus is a genus of North American amphibian commonly referred to as the North American spadefoots, southern spadefoots, or eastern spadefoot toads. They differ greatly from true toads by having eyes with vertical pupils, no parotoid gland, and relatively smooth skin. Their most distinctive feature is a spade-like projection on their hind feet, from which their common name is derived. This projection enables spadefoot toads to dig in loose soils with ease. Its scientific name means ‘spade-foot’ as well, from the Ancient Greek skaphís and pous.

<i>Spea</i> Genus of amphibians

Spea is a genus of North American amphibian commonly referred to as the western spadefoot toads. They differ greatly from true toads by having eyes with vertical pupils, no parotoid glands, and relatively smooth skin. Their most distinctive feature is a spade-like projection on their hind feet, from which their common name is derived. This projection enables spadefoot toads to dig in loose soils with ease. Its name is from the Ancient Greek speos

<span class="mw-page-title-main">Texas toad</span> Species of amphibian

The Texas toad is a species of medium-sized toad that occurs in the southern United States and northern Mexico. It breeds in temporary water pools after heavy rains.

<span class="mw-page-title-main">Couch's spadefoot toad</span> Species of amphibian

Couch's spadefoot toad or Couch's spadefoot is a species of North American spadefoot toad. The specific epithet couchii is in honor of American naturalist Darius Nash Couch, who collected the first specimen while on a personal expedition to northern Mexico to collect plant, mineral, and animal specimens for the Smithsonian Institution.

<span class="mw-page-title-main">Plains spadefoot toad</span> Species of amphibian

The plains spadefoot toad is a species of American spadefoot toad which ranges from southwestern Canada, throughout the Great Plains of the western United States, and into northern Mexico. Like other species of spadefoot toads, they get their name from a spade-like projection on their hind legs which allows them to dig into sandy soils. Their name, in part, comes from their keratinized metatarsals, which are wide instead of "sickle shaped". The species name translates as buzzing leaf shaped. This refers to the species' distinguishing features; its buzzing mating call, and its leaf-shaped digging metatarsals. It was first described by Cope in 1863.

<span class="mw-page-title-main">New Mexico spadefoot toad</span> Species of amphibian

The New Mexico spadefoot toad is a species of American spadefoot toad found in the southwestern United States and Mexico. Like other species of spadefoot toad, they get their name from a distinctive spade-like projections on their hind legs, which enable them to dig in sandy soils. Spea multiplicata can be identified by its wedge-shaped spade. Some sources also refer to the species as the Mexican spadefoot toad, desert spadefoot toad or southern spadefoot toad.

<i>Scaphiopus holbrookii</i> Species of amphibian

Scaphiopus holbrookii, commonly known as the eastern spadefoot, is a species of American spadefoot toad endemic to North America. It is not considered a true toad.

<span class="mw-page-title-main">Yosemite toad</span> Species of amphibian

The Yosemite toad is a species of true toad in the family Bufonidae. Endemic to the Sierra Nevada of California, the species ranges from the Alpine County to Fresno County. Yosemite toads are only found in the montane to subalpine elevational zone of 1,950–3,445 m (6,398–11,302 ft) asl. The Yosemite toad is similar to the nearby western toad, but in many ways adapted to a high elevation lifestyle. It was initially described during the Grinnell Survey of California, by an undergraduate student of Joseph Grinnell named Charles Camp.

<span class="mw-page-title-main">Arizona toad</span> Species of amphibian

The Arizona toad is a species of toad in the family Bufonidae. It is endemic to the south-western United States, where its natural habitats are temperate lowland forests, rivers and streams, swamps, freshwater marshes, freshwater springs, ponds, open excavations, irrigated land, and seasonally flooded agricultural land.

Pelobates varaldii, the Moroccan spadefoot toad, Moroccan spadefoot, or Varaldi's spadefoot toad, is a species of frog in the family Pelobatidae. As currently known, it is endemic to the coastal north-western Morocco, although there is an unconfirmed record from the Spanish territory of Melilla that could possibly represent this species. The specific name varaldii honours Marcel Varaldi who collected amphibians and reptiles in Morocco.

<span class="mw-page-title-main">Great Basin spadefoot</span> Species of amphibian

The Great Basin spadefoot is an amphibian in the family Scaphiopodidae. It is 3.8 to 6.3 centimetres long and is usually colored gray, olive or brown. Great Basin spadefoot toads have adapted to life in dry habitats. They use the hard, keratinized spade on each foot to dig a burrow, where they spend long periods during cold and dry weather. They are opportunistic hunters and will eat anything they can subdue. While their tadpoles have numerous predators, adults are able to produce skin secretions that deter enemies.

<i>Pelobates syriacus</i> Species of amphibian

Pelobates syriacus, the eastern spadefoot or Syrian spadefoot, is a species of toad in the family Pelobatidae, native to an area extending from Eastern Europe to Western Asia.

References

  1. IUCN SSC Amphibian Specialist Group (2022). "Spea hammondii". IUCN Red List of Threatened Species . 2022: e.T59045A53972800. doi: 10.2305/IUCN.UK.2022-2.RLTS.T59045A53972800.en . Retrieved 12 May 2023.
  2. 1 2 3 Frost, Darrel R. (2019). "Spea hammondii (Baird, 1859)". Amphibian Species of the World: an Online Reference. Version 6.0. American Museum of Natural History. Retrieved 5 March 2019.
  3. 1 2 Beolens, Bo; Watkins, Michael & Grayson, Michael (2013). The Eponym Dictionary of Amphibians. Pelagic Publishing. p. 89. ISBN   978-1-907807-42-8.
  4. Conant, Roger. 1975. A Field Guide to Reptiles and Amphibians of Eastern and Central North America. Houghton Mifflin. Boston.
  5. 1 2 Neal, Kevin M; Fisher, Robert N; Mitrovich, Milan J; Shaffer, H Bradley (31 December 2020). Garrick, Ryan (ed.). "Conservation Genomics of the Threatened Western Spadefoot, Spea hammondii , in Urbanized Southern California". Journal of Heredity. 111 (7): 613–627. doi: 10.1093/jhered/esaa049 . ISSN   0022-1503. PMID   33245338.
  6. 1 2 Baumberger, Katherine L.; Backlin, Adam R.; Gallegos, Elizabeth A.; Hitchcock, Cynthia J.; Fisher, Robert N. (25 May 2020). "Mitigation Ponds Offer Drought Resiliency for Western Spadefoot (Spea hammondii) Populations". Bulletin, Southern California Academy of Sciences. 119 (1): 6. doi:10.3160/0038-3872-119.1.6. ISSN   0038-3872. S2CID   218891199.
  7. Morey, Steven R.; Reznick, David N. (January 2004). "The relationship between habitat permanence and larval development in California spadefoot toads: field and laboratory comparisons of developmental plasticity". Oikos. 104 (1): 172–190. doi:10.1111/j.0030-1299.2004.12623.x.
  8. 1 2 "Project: Western Spadefoot Habitat Restoration and Seasonal Pool Creation". California Natural Resources Agency. 9 May 2023. Retrieved 9 May 2023.
  9. 1 2 Nguyen, Lilly (12 December 2019). "Coastal Commission approves 8 toad pools and habitat restoration at Crystal Cove State Park". Los Angeles Times. Retrieved 9 May 2023.