Non-Riparian Wetlands

(Playas, Alkali Lakes, Ponds, Lakes, and Marshes)

This habitat is located within the Llano Estacado, south of the Canadian River, covering most of Quay, Curry, Roosevelt, and Lea counties in the Pecos and Staked Plains Physiographic Area. Playas are part of a larger wetlands system that covers five states in the southern Great Plains. Approximately 85% of the playas in these five states are in New Mexico and Texas (Haukos and Smith 1997). In New Mexico, there are estimated to be from 1700 playas (Nelson et al.1983) to about 2460 (Guthery et al. 1981), mostly in the Llano Estacado (Haukos and Smith 1997).

Playas are shallow, closed systems, generally with clay bottoms. Historically, they received water only from rain and surrounding rainfall runoff. Tailwater from surrounding irrigated agricultural lands is currently an additional water source. This may cause playas to flood more frequently than prior to initiation of agriculture (Haukos and Smith 1997).

While playas occupy only about 2% of the land, they collect flood waters from approximately 90% of the region and are important for storm water catchment in urban areas. Few playas are directly connected to groundwater but are critical recharge points to the southern portions of the Ogallala Aquifer, filtering and recharging 20-80% of collected water to the aquifer (Haukos and Smith 1997).

Playas are characterized by the ephemeral nature of rainfall in this area, averaging about 14-16 in (36-41 cm) per year (Jones 1996). During wet periods, vegetation characteristic of permanent ponds and marshes develops. When this occurs, playas become an important stopover point for migrating waterfowl and shorebirds, as well as a water source for all birds in the area. Playas with moist soil, but no standing water, develop vegetation that is dominated by forbs. This may produce seeds important to migrating sparrows and finches. Playas that remain mostly dry develop vegetation similar to that of the surrounding grasslands. Playa vegetation is dependent upon the wet and dry cycles for rejuvenation. A decrease in vegetative diversity will result in a corresponding decline in wildlife diversity. For groundwater recharge and bird value, playas should be allowed to function naturally within an agricultural landscape (Haukos and Smith 1997).

Historically, this area contained short- and mid-grass prairie. Cattle grazing began here in the 1870’s. Agricultural cultivation began around the 1920’s. The advent of irrigation in the late 1940's allowed a larger percentage of land to be farmed (Haukos and Smith 1997).

Sedimentation from cropland has been identified as a major threat to playas. Sediment fill results in increasingly xeric conditions. Other threats include pesticide and herbicide runoff. One study (Price et al. 1989) found that applying tebuthiuron at higher levels than 1.9 lbs/ac (2.2kg/ha) on rangelands adversely affect playa algal communities. Dumping of contaminated water from oil field operations has killed large numbers of birds (Nelson et al. 1983). Construction of irrigation pits within playas changes the natural wet cycles and the surface area, and affects plant communities. Edges become more xeric with prairie vegetation dominating, while the pit becomes more perennial with concurrent permanent marsh vegetation. Overgrazing of playas reduces plant diversity and increases species such as buffalo grass (Buchloe dactyloides), cockleburr (Xanthium strumarium), and burr ragweed (Ambrosia grayi) (Guthery et al. 1982). Elimination of grazing around playas increases habitat for waterfowl and shorebirds and reduces the encroachment of less desirable vegetation, erosion, increased turbidity, and sedimentation (Guthery et al. 1982).

Over 99% of playas are privately-owned (Haukos and Smith 1997). Therefore, education about the benefits of playas is highly important.

These lakes, also commonly called playas, are shallow, closed basins that receive water from rainfall. They are more common within the Chihuahuan Desert and Colorado Plateau Physiographic Areas in New Mexico, although a few occur in the Mogollon Rim and on the Pecos and Staked Plains.

They function in a similar manner to the playas described above. Average yearly rainfall is generally from 8 to 12 inches. Because these lakes and basins are not normally associated with agricultural areas, agricultural tailwater rarely affects these areas. They are usually filled with water less often than non-saline playas.

Ground cover is sparse in alkali lakes. Often, there is enough standing water to prevent perennials from taking hold. Burrowgrass (Scleropogon brevifolius) and occasionally forbs, usually from the surrounding grassland, occupy the edges. In the northwestern quadrant, fourwing saltbush (Atriplex canescens) and shadscale (Atriplex confertifolia) codominate and ground cover may be higher than in southern areas. Most of the forbs belong to the goosefoot family, Chenopodiaceae. If the southern lakes’ edges are sandy, shrubs may include mesquite (Prosopis sp.) or soaptree yucca (Yucca elata). Annuals, such as bitterweed (Hymenoxys odorata), often form pure stands on the dried playa beds. If edges are not sandy, tarbush (Flourensia cernua) may dominate. Sacaton associations are often found in transition zones to surrounding grasslands (Dick Peddie 1993).

Large areas with dense stands of fourwing saltbush are typical of closed-basin vegetation. Occasionally, pale wolfberry (Lycium pallidum) is a codominant. Common forbs are red sage (Kochia americanca), Atriplex patula, and A. corrugata. Greasewood (Sarcobatus vermiculatus) can be found dominating upper portions of the basins. On the closed basins near White Sands, Reid (1980) found large areas dominated by Coldenia hispidissimus, with scattered allthorn (Koerbelinia spinosa) and squawbush. Forbs in these areas, especially in south-central and southeastern New Mexico, are gypsum-soil adapted, including gyp moonpod (Selinocarpus lanceolatus), gyp grama (Bouteloua breviseta), gyp dropseed (Sporobolus nealleyi), and the mustard Nerisyrenia camporum (Dick-Peddie 1993). Trees are rare in these areas although salt cedar (Tamarix spp.) can be found, sometimes in great abundance.

Vegetation does not generally differ from small seeps to large lakes, except with increased water depth. Therefore, all are included in this section. Additionally, this vegetation may occur in playas and alkali lakes if water is present for long enough periods of time to allow emergent growth. Generally, cattails appear first, followed by bulrushes, rushes and sedges (Dick-Peddie 1993).

In wetland areas, vegetation in shallow water or very moist soil consists of grasslike plants such as sedges (Carex spp., etc.), bulrushes (Scirpus spp.), rushes (Juncus spp.), and cattails (Typha spp.) along with nongrasslike forms such as water plantain (Alisma sp.) and arrowhead (Sagittaria sp.). Floating-leaf plants, such as water shield (Brasenia sp.), pondweed (Potamogeton sp.), water fern (Azolla sp.), duckweed (Lemna sp.), watercress (Rorippa sp.), and smartweed (Polygonum sp.), develop as water becomes deeper. Floating algae (phytoplankton) may also be present. These two associations of plants comprise the majority of marsh vegetation. If deeper water is present, submersed plants including milfoil (Myriophyllum sp.), waterweed (Elodea sp.), hornwort (Ceratophyllum sp.), stoneworts (Chara spp. and Nitella spp.), bladderwort (Utricularia sp.) and fixed algae (various genera) occur (Dick-Peddie 1993).

Considerable variation exists in dominant species. Some lakes naturally do not contain all associations. Many man-made lakes maintain relatively stable water levels and support two or more associations of aquatic vegetation. Some man-made lakes are subject to large and rapid changes in water levels and rarely have stable plant communities. The vegetation that occurs in unstable lakes contains fewer plant species than in lakes with stable water levels (Dick-Peddie 1993). These are the larger reservoirs found along the San Juan, Rio Grande and Pecos Rivers.

Non-riparian wetlands are used by breeding, long-legged waders, waterfowl and shorebirds. Use of these wetlands by these species is dependent on the amount of vegetation and water depth rather than elevation or location. Exceptions are Snowy Plover and Least Tern, which must have relatively level, alkali flats, free of vegetation near the water.

These wetlands serve as a source of water for all birds in the surrounding areas. In addition, these wetlands are extremely important for migrating and wintering birds. Waterfowl and Sandhill Cranes depend on wetlands at Bosque del Apache National Wildlife Refuge near Socorro. Larger reservoirs, built for water storage rather than flood control, are important for piscivorous waterbirds such as loons, grebes, some ducks and cormorants. The headwaters of Elephant Butte and Caballo lakes are a breeding area for many colonial waterbirds.

The shorter rush and taller grass areas bordering these wetlands are important breeding areas for smaller ducks such as Cinnamon and Blue-winged Teal and rails, such as Sora. Currently, these birds are not considered at risk and, therefore, this habitat niche is not specifically addressed in the following sections. Western and Clark’s Grebe are considered together in this plan due to a lack of information about differences in their breeding habitat and because there are instances of interbreeding in New Mexico.

Impacts to these habitats include 1) grazing, 2) draining, 3) water diversion, 4) agricultural, urban and industrial runoff and waste, and 5) upslope development for housing or industrial use.

These lands are owned and managed by a variety of private landowners, Native American jurisdictions, and state and federal agencies. Some of the most important wetland areas are managed by the National Wildlife Refuge System and include Bitter Lake, Bosque del Apache, Las Vegas and Maxwell National Wildlife Refuges.

Physiographic Areas covered: Mexican Highlands, Chihuahuan Desert, Pecos and Staked Plains, Mogollon Rim, Colorado Plateau, Southern Rocky Mountains

Table 1. Alkali Lakes Priority Species

Table 1. Other Non-riparian Wetlands Priority Species

Bird Habitat Requirements, Population and/or Habitat Objectives:
(in taxonomic order)

• freshwater lakes with extensive area of open water, bordered by emergent vegetation
• open water must be relatively extensive compared to amount of vegetation (D. Stahlecker pers.comm.)
• nests most often in emergent vegetation almost always in water over 9.7 in (25cm) in depth and up to 9.8 ft (3m); may use open water areas with extensive submersed vegetation (NMPIF)
• prefers nesting sites with some break in wave action/less intense waves than open water

• marshes with tall, emergent vegetation, especially cattails
• will occasionally nest in tall (over 1ft/0.3m) grass surrounding a wetland basin but not documented in new Mexico
• prefers shallow water (4 in/10cm) and dry cattail habitats, avoiding deep-water cattails and river bulrush
• minimum patch is 0.25ac (0.1ha) (NM PIF); 24.7ac (10ha) is preferable
• nests constructed in cattails over water concealed from above and sides by surrounding vegetation

• in the West, T = -4.8%, p = 0.00, N = 96, RA=0.44 (Sauer et al. 1997)
• maintain annual detectable populations at known breeding areas
• establish or maintain blocks of 24ac (9.7ha) patches of habitat to sustain one or more breeding pair to ensure sustained breeding

• in the West, T = 8.2%, p = 0.01, N = 61, RA=0.22 (Sauer et al. 1997)
• maintain four known breeding pair in Sierra and Colfax counties
• increase number of breeding territories to at least 10 by 2019
• maintain prairie dog towns within foraging range of bald eagle nesting areas
• reduce or eliminate disturbance to nest sites
• maintain stable or increasing reproductive success rate

• in the Central United States (the subspecies in the interior central U.S. also nests in New Mexico), T = -12.9%, p = 0.02, N = 15, RA=0.24 (Sauer et al. 1997)
• maintain current population at Bitter Lake NWR
• maintain average of 5 breeding pairs
• establish 1 additional breeding population in the Pecos watershed by 2019
• maintain nesting success of 1 fledgling per pair/per year
• maintain or draw down on areas adjacent to alkali flats

Grazing - Reduce grazing in wetland areas by fencing off patches of emergent vegetation. Eliminate grazing or sharply reduce area of access to water during dry years.

Waste treatment/dumping - Encourage city sewage treatment facilities that create marshes as secondary or tertiary treatment. Eliminate industrial waste dumping into playas.

Pesticide use - Pesticides have been shown to have potentially detrimental effects on birds and bird reproductive success. Pesticide use should be limited to appropriate levels.

Wetland maintenance - Reduce or eliminate draining and filling wetlands. Maintain existing wetlands with an undeveloped buffer zone when developing areas for residential or industrial use.

Research and monitoring needs:

Table 2. Non-Riparian Wetlands Priority Species: Habitat Factors