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RECOVERY PLAN FOR THE

OWENS , RADIOSUS

Published by

U.S. ana Wildlife Service

Portland, Oregon

Approved:

Regional Director, U.S. Fish and Wildlife Service

9Z, 7fy Date THIS IS THE COMPLETED RECOVERY PLAN OF THE . IT HAs BEEN

APPROVED BY THE U.S. FISH AND WILDLIFE SERVICE. IT DOES NOT

NECESSARILY REPREsENT OFFICIAL POSITIONS OR APPROVALS OF COOPERATING

AGENCIES AND IT DOES NOT NECESSARILY REPRESENT THE VIEWS OF ALL

INDIVIDUALS INVOLVED IN THE PLAN FORMULATION. THIS PLAN IS SUBJECT TO

MODIFICATION AS DICTATED BY NEW FINDINGS AND CHANGES IN SPECIES STATUS

AND COMPLETION OF TASKS DESCRIBED IN THE PLAN. GOALS AND OBJECTIVES

WILL BE ATTAINED AND FUNDS EXPENDED CONTINGENT UPON APPROPRIATIONS,

PRIORITIES AND OTHER BUDGETARY CONSTRAINTS.

LITERATURE CITATION SHOULD READ AS FOLLOWS;

U.S. FISH AND WILDLIFE SERVICE. 1984. RECOVERY PLAN FOR THE

OWENS PUPFISH, CYPRINODON RADIOSUS. U.S. FISH AND WILDLIFE

SERVICE, PORTLAND, OREGON. 47 pp.

ADDITIONAL COPIES MAY BE OBTAINED FROM;

FISH AND WILDLIFE REFERENCE SERVICE

1776 E. JEFFERSON STREET, FOURTH FLOOR

ROCKVILLE, MARYLAND 20852

TELEPHONE; 1-800-582-3421

(IN MARYLAND; 1-301-468-1737) Acknowledgments

The authors of this recovery plan are Thomas L. Taylor,

Department of Fish and Game (present address: California Department

of Parks and Recreation, P.O. Box 2390, Sacramento, California 95811) and Jack E. Williams, U.S. Fish and Wildlife Service (2800 Cottage

Way, Room E-1823, Sacramento, California 95825).

We are greateful to the reviewers who provided technical assistance on earlier drafts of this plan. In particular, we wish to acknowledge

Louis A. Courtois (California Department of Fish and Game,

Sacramento), Larry L. Eng (California Department of Fish and Game,

Sacramento), Gail C. Kobetich (U.S. Fish and Wildlife Service,

Sacramento), Robert R. Miller (The University of Michigan, Ann Arbor),

Peter B. Moyle (University of California, Davis), Edwin P. Pister

(California Department of Fish and Guile, Bishop), Donald W. Sada (U.S.

Fish and Wildlife Service, Reno), and Darrell M. Wong (California

Department of Fish and Game, Bishop). Were it not for the tireless efforts of Edwin P. Pister and other members of the Desert

Council, the Owens pupfish and its habitats would have vanished long ago.

Cover Photograph: Fish Slough with White Mountains in the background.

Photograph taken 30 March 1981 by Thomas L. Taylor. Owens Pupfish Recovery Plan

Executive Summary

1. Point or condition when species can be considered recovered.

Species can be considered recovered when five populations, each

with a minimum overwintering population of SUU, have been

establisned in five separate areas. The populations must have

been free of threats for a period of five consecutive years with

no foreseeable threats in the near future.

2. What must be done to reach recovery?

Present populations need to be secured. Three new retugia need

to be established and their habitats secured.

3. What specifically must be done to meet needs of #2?

Habitat and populations will be secure When. I) exotic species

are controlled or eliminated, 2) emergent vegetation is

controlled, and 3) sufficient water quality is guaranteed. For

new refugia, habitats must be secured, management plans snould be

developed and implemented, and puptish should be introduced. 4. What management/maintenance needs nave been identified to keep

tne species recovered?

Management plans will be developed and implemented. A monitoring

program is proposed. Also, public education and law enforcement

progrems (including periodic review of applicable laws and

regulations) are included. TABLE OF CONTENTS

Page

PART I. INTRODUCTION ...... 1

Taxonomy ...... 2

Description ...... 2

Ecology ...... 4

Historic Distribution and Decline . 6

Causes of Decline ...... 8

Current Status and Conservation Efforts ...... 9

PART II. RECOVERY ...... 16

Objectives ...... 16

Step-down Outline ...... 18

Narrative ...... 22

Literature Cited ...... 38

PART III. IMPLEMENTATION SCHEDULE ...... 41

APPENDIX ...... 47

List of Agencies Asked to Submit Review Comments. 47

OMENS PUPFISH RECOVERY PLAN

PART I. INTRODUCTION

The Oweris pupfish ( Cyprinodon radiosus) orginally ranged throughout

much of the , California. They were once abundant in

shallow marshy areas and springs along the from Fish

Slough in Mono County to Owens Lake in Inyo County, but domestic and

agricultral use of the springs and water diversions have eliminated

most of the habitat of the Owens pupfish. The introduction of exotic

predator and competitors has also contributed to the extirpation of

populations. For 14 years the Owens pupfish was believed to be

extinct, but in 1956 a small population was "discovered" in Fish

Slough. The significance of this population was not realized until it

was redi scovered in 1964. This small population has been the source

for all Owens pupfish populations that subsequently have been reestablished and exist today (Miller and Pister 1971).

The depl eted status of this species has been widely recognized in the

governmental and scientific communities. The U.S. Fish and Wildlife

Service listed the Owens pupfish as endangered in 1967 (Federal

Register 32:400i). The State of California also lists this species as endangered (California Department of Fish and Game 1980) as does the

American Fisheries Society (Deacon et al. 1979). 2

Taxonomy

The Owens pupfish was orginally referred to as C. macularius (Kennedy

1916). This taxonomic identification was questioned when sufficient

information was collected to indicate that pupfish in the Amargosa and

Owens River drainages should be considered taxonomically distinct from

those in the system (Miller 1943). In 1948, Miller published his findings describing the Owens pupfish, _C. radiosus, as a new species endemic to the Owens Valley. The type locality for the

Owens pupfisn is the northwest spring of Fish Slough (Miller 1946), which is currently within the Owens Valley Native Fish Sanctuary.

Relationships of C. radiosus, are considered to ue closer to the ancestral form of 4prinodon (cf. macuiarius), which entered the Owens and Deatn Valley areas during the Pliocene, than with C. nevadensis or

C. salinus (Miller 1981).

Description

The Owens pupfish is a small, deep-bodied fish with a laterally compressed shape. Maximum total length for this species is 60 mm (2

3/8 in) but most are typically 30 to 45 mm (11/4 to 1 3/4 in). i4prinodon radiosus closely resembles _C. _macularius _ _ _ _ except that they lack the spine-like projections on the circuli of the scales and the interspaces among the circuli possess prominent reticulations (Miller

1948). The structural scale pattern of C. radiosus is similar to that of C._ nevadensis and _C. _diabolis _ _ _ of the Amargosa River drainage as 3 well as C. salinus and C._ milleri of Death Valley. Cyprinodon radiosus differs from the in the Amargosa and Death Valley regions by possessing a very anteriorly positioned dorsal fin

(predorsal length averages 53.3% of SL 1 in males and 54.8% in females) a thickened first dorsal fin ray, a higher average number of dorsal (i

= 11.1), anal (i =10.4), and pelvic (i = 6.9) fin rays; a much more slender head (averages 21.9% of SL), and a larger caudal peduncle

(averages 28.6% of SL in males and 26.2% in females) (Miller 1948).

The species is illustrated in Miller (1948:Plate IX), Moyle (1976.257) and Soltz and Naiman (1978:12-13).

Owens pupfish, like other species of Cyprinodon, are sexually dichromatic. Adult males possess a blue color overlying an olive color dorsally and slate ventrally (Miller 1948). Lateral bars are deep purplish with some gold color among the posterior bars. Lower parts of the head are silver and blue. The dorsal and anal fins are blue with an orange-amber border. The caudal fin may or may not possess a terminal black band. Miller (1948) characterizes the color of females as deep olive with brown lateral blotches and vertical bars shade toward purplish. The fins are yellowish with pale margins on the dorsal and anal. An ocellus is present on the posterior portion of the dorsal fin in females. Breeding colors of the Owens pupfish are described in detail by Miller and Pister (1971).

1 Standard length (SL) is the distance from the tip of the snout to

the end of the vertebral column. 4

Except for color differences, tne Owens puptisn exnibits little sexual

dimorphism. However, Miller (1948) noted that males possessed a

deeper body, head, and caudal peduncle than females. The caudal

peduncle is longer in males and the fins, particularly the anal, are

larger. Sexes exhibit little variation in other mensural characters.

Ecology

Male pupfish are larger than females and are territorial. The

spawning season extends from April to October depending on weather

conditions. Once the water temperature exceeds 2O°C, spawning begins.

Males become territorial and bright blue in color when spawning.

Males defend their territory from otner male pupfish as well as all

other fish species. Females that enter a male's territory are

courted. Eacn female can spawn a total of bi.) to 200 eggs per season, but rarely lays more than one or two eggs at a time (Barlow i961).

The eggs are transparent, demersal, and approximately 2 mm in diameter. They hatch in about 7 to 10 days, depending on water temperature. In captivity, pupfish larvae are large enough to feed from the day of hatching on small food items the size of brine shrimp nauplii (Great- and Haycock 1971). In the wild, pupfish fry live along the shorelines where the warm water supports abundant quantities of food. The fish mature in 3 to 4 months, permitting one spawning prior to their first overwintering period.

Runoff from winter and spring rains creates extensive shallow areas wnich provide excellent spawning and nursery habitat for the pupfish. 5

During spring, the size of the pupfish population increases dramatically as this habitat enlarges and warms (Brown 1971).

Historically, populations usually reached their peak during mid- to late-summer prior to the seasonal desiccation of marshy habitat.

Pupfish are omnivorous opportunists who feed on , aquatic insects, , plankton, terrestrial insects that fall into the water, and even their own dead (Bunnell 1970). Kennedy (1916) analyzed the stomach contents of 14 pupfish and found the primary food item (90%) to be chironomid larvae. Owens pupfish are not piscivorous, but like other pupfish species, C. radiosus are predacious on their own eggs. Their small size and tolerance to temperature and extremes permits the pupfish to forage in habitats too hostile for most other fish species. These areas are usually nursery grounds for insects, which provide an excellent food supply unavailable to other native adult fish species. Mosquitofish can also utilize these shallow areas and can effectively compete with the Owens pupfish. However, male pupfish can harass other species to death if they trespass into established pupfish territories (Hiscox

1978).

Basic habitat requirements for the Owens pupfish consist of a small amount of good quality water, some vegetation and a silt- or sand-covered bottom. Historically, pupfish were collected near the margins of large tule marshes in wide, shallow (8-15 cm) sloughs with abundant aquatic vegetation and in springs along the Owens River

(Miller and Pister 1971). 6

Typical habitat for the Owens puptisn are snallows witn sparse

cattails ( .) and bulrush ( Scirpus) ana a sand-silt-detritus

bottom. These snallows are associated with relatively deeper water

where the adult pupfish establisn territories and spawn. Dense tule

stands seem to exclude pupfish, but the shallow areas adjacent to the

Owens River probably never became densely vegetated as a result of

their annual cycle of flooding and drying.

Historic Distribution and Decline

Owens pupfish orginally were found in the Owens River and adjacent springs and sloughs from the springs at Fish Slough in Mono County, to as tar south as, but not in, Owens Lake, Inyo County, anu in the springs around the lake (Figure 1). Miller (1948) and Miller and

Pister (1971) described a progressive decline in the population of

Owens pupfish from i9i6 through 1941.

In a 1934 survey of the Owens Valley, Carl L. Hubbs found only a few fish in pools along the big bend areas of the Owens River northeast of

Bishop where Clarence H. Kennedy had observed large schools of Owens pupfish in 1915 (Kennedy 1916, Miller and Pister 1971). During their survey, the Hubbs party could find no Owens pupfisn along the Owens

River between Laws and Bishop. During the 1930's, springs at Fish

Slough provided the last retugium for the Owens puptish. But by 1937,

Fish Slougn was primarily- inhabited by carp ( Cyprinus carpio) and ( Micropterus salmoides) (Miller and Pister i971). 7

r*Vr.t.'6?"•!..e4 .. ,, • Historical Distribution Current Distribution

Lake Crowley

Owens Valley Native Fishes (Salictuary... BLM Spring Ref ugium - r

BISti OP

cNWarm Springs * Refugium •?.

BIG PINE z

Tinemaha Reservoir

INDEPENDE

0 5 10 Mau'

Figure 1. Present and historical distribution of the Owens pupfish. Mono and Inyo Counties, California. 6

Surveys conducted in 1942 at Fish Slough failed to find any Owens

pupfish and the species was presumed extinct. The species was thought

to be extinct until I95u, when California Department of Fish and Game

personnel discovered a small population in shallow ponds along the

east side of Fish Slough (Miller and Pister 1971). This population

was largely torgotten until its "rediscovery" in .1 04. At that time,

tile population was estimated at only 2Uu individuals.

In addition to the puptisn, Owens sucker (Latostomus tumeiventris),

Owens tui chub ( Gila bicolor snideri) and speckled dace (Rhinichthys

osculus sspp.) are endemic to the Owens basin. Whereas the Owens

sucker has remained common, the Owens tui chub has declined

substantially and was proposed in 1984 for endangered status (Federal

Register 49:10959-1(J962). Although their taxomony is uncertain, one

or more of the local forms of speckled dace appear to have been

extirpated.

Causes of Decline

Shallow marshy areas adjacent to the Owens River were destroyed as

upstream impoundments and diversions prevented normal tlooaing cycles.

Dams aria canals diverted most or the water of the Owens River into the

Los Angeles aquaduct and subsequently out of the Owens Valley. Other

dams and diversion structurts on tne Owens River were built to

distribute water for agricultural use within tne Owens Valley.

Collectively these impoundments and diversions drastically altered tne habitat of the Owens pupfish. The introduction of exotic species also contributed to the decline of the Owens pupfisn. Largemouth bass,

Drown trout ( Salmo trutta), mosquitofisn and other exotics have been introduced into the Owens Valley. Largemouth bass, and crayfish ( Procambarus clarki) are predators on Owens pupfish, while mosquitofish probably compete with the Owens pupfish for food and space and may predate on younger individuals. Crayfish are also effective predators on pupfish eggs.

Currently the pupfish are not secure in any of their three refugia

(see below, Current Status and Conservation Efforts). Each refugium is vulnerable to disruption from various land uses. Ground water pumping from agriculture could threaten the aquifers supplying water to remaining springs. Also, largemouth bass, mosquitofish and crayfish have been planted in these refugia by individuals or agencies unaware of or unconcerned with the plight of the Owens puprish.

Vandals have destroyed habitat or structures built to create and maintain the habitats.

Current Status and Conservation Efforts

The Owens pupfish has been extirpated from much of its historic range within the Owens Valley. As of July 1984, three Owens pupfish populations exist in two man-modified refugia. These populations are the Owens Valley Native Fish Sanctuary and BLM Spring in Fish Slough, and Warm Springs (Figures 1, 2 and 3). 10

During 1968 and 1969, tne California Department of Fish and Game and

the Los Angeles Department of Water and Power created an 8.5 hectare

(2i acre) tenced sanctuary in Fish Slough containing a 2.3 hectare

(5.6 acre) pond. This area was officially declared the Owens Valley

Native Fish Sanctuary (OVNFS) by the Fish and Game commission in 1970.

It provides protected habitat for an Owens Valley tom ot speckled

dace, Uwens tui chub, and Owens sucker as well as Owens pupfish.

A reduction in water flow from the springs at what is now the Owens

Valley Native Fish Sanctuary in the summer of 1969 posed a threat to continued survival of the pupfish within the area, and additional refuges were created, one at BLM Spring, on the east side of Fish

Slough, during the summer of 1969, and the other at Warm Springs, 9 Km northeast of big Pine, during tne spring of 1970 (Figures 1 and 2).

Although the retugia in Fish Slough were designed to prevent invasion by exotic fishes, largemoutn bass have been introduced uy man above the fish barriers and have invaded the slough. The largemoutn bass preyed extensively on the pupfish and greatly reduced their numbers in

Fish Slough. In 1980, a second dam was added to the OVNFS 200 m below the original structure, which created a second impoundment (Figure 3).

At BLM Spring, in the southeast portion ot Fish Slough, a second dam downstream from the original structure was rebuilt in October, 1981.

Two shallow pools were created on either side of the stream channel upstream of the dam to provide pupfish habitat. .4 NORTHEAST SPRING MT.•• • * G * SOO A S • I! • OWENS VALLEY • • NATIVE FISH " IC • SANCTUARY • • f• •

16 a° 40 • 1. Cn

11070:4 • te • • e 110 f. • st

4. 1R

BLM SPRING Ike LI aT) •■-; •

Bishop 4ini SW

River

FIGURE 2. THE OWENS VALLEY NATIVE FISH SANCTUARY AND THE SURROUNDING FISH SLOUGH AREA.

12

550'

Spj.irt.p ‘ /'.

- R

\ Spr,inj \ ... \ # 1 \ Q / b I 1 in ct ( I 1 0 \ t 1 \ \ I t \ i % %.*... 1 \ '..... \ 2 I J

1 050 ' OWENS VALLEY NATIVE FISH SANCTUARY

Figure 3. Habitat improvement work at - tecondary the Owens Valley Native Fish Dam Structure Sanctuary. 13

Warm Springs refugium is a small pond formed by a single small dam and

fed by a thermal spring. It is located on Department of Water and

Power property north of Big Pine adjacent to the White Mountains. The

Warm Springs Refugium has been free from introduced fish predators;

however, crayfish and mosquitofish (Gambusia affinis) have found their

way into the refugium and have required control measures in the past

to protect the pupfish population. Mosquitofish were successfully eradicated from Warm Springs in 1979, but have sporadically reappeared since then, presumably through illegal introductions.

Fish Slough is a unique wetland in an arid environment. The

University of California is eager to have the Fish Slough area included in its Land and Water Reserves System (UC LWRS) as an

Ecological Study Area. The uniqueness of Fish Slough goes beyond the

Owens pupfish. The Fish Slough milk vetch ( Astragalus lentiginosus var. piscinensis) is known only from Fish Slough. Several other rare plant species or disjunct plant populations also occur in the Fish

Slough area: Calochortus excavatus, Centaurium namophilum var. nevadensis, Fimbristylis thermalis, Spartina gracilis,

Dodecatheon pulchellum, and Astragalus argophyllus var. argophyllus.

An undescribed species of mollusc, the Fish Slough snail

( Fontelicella sp.), is known to occur in the OVNFS spring outflow and in Northeast Spring. Collectively, the occurrence of these unusual species demonstrates the overall uniqueness of this area. In recognition of these qualities, the Bureau of Land Management has proposed an Area of Critical Environmental Concern status for 35,926 14

acres encompassing Fish Slough and its surrounding hydrologic basin.

In conjunction with the U.S. Fish and Wildlife Service, California

Department of Fish and Game, University of California and Los Angeles

Department of Water and Power, the Bureau of Land Management is preparing a management plan for the Fish Slough area.

In December 1982, the U.S. Congress passed HR. 2475, which provided for a 82 hectare (202 acre) land exchange between a private party and

BLM. This exchange nas placed the last parcel ot private land within

Fish Slough into public ownership. Thus, maintenance ot the integrity ot Fish Slough appears attainable.

Present refugia for the Owens pupfish provide warm water of good quality (Courtois and Tippets 1979). Natural fluoride levels of 1.5 mg/1 at BLM Springs may be a potential problem as this is at the reported maximum acceptable fluoride level for aquatic life (McKee and

Wolf 1963). Sufficient habitat for the recovery of Owens pupfish populations can be created and managed if there is adequate water and protection from exotic fishes.

The amount ot suitable habitat presently available for tne Owens pupfish is but a small percentage of the original amount of habitat in the Owens Valley. They have been eliminated from a large portion of the Owens Valley and are now restricted to three small man-modified refugia located at the northern end of the valley. These small, isolated populations constitute but a tiny fraction of the millions of 15

pupfish that must have once inhabited the flooded meadows of the Owens

Valley. Presently, where suitable habitat is found, exotic fishes

occur in abundance and pose threats to efforts to restore pupfish

populations. Because of habitat loss and the spread of exotic fishes

in Owens Valley, transplant efforts will have to include sites in adjacent Adobe Valley, where good habitat still exists. 16

MKT II. litGUVERY

OD4ectives

The primary objective of this recovery plan is to improve the status

or the Owens puptish to the point when it can ue removed from tne List

of Lndanyered and Tnreatened Wildlite. There are currently three

populations in the Owens valley. Two ot these are located in close

proximity to each other in Fish Slouyh an will De considered as one

population for the purposes of this discussion, as any event attectiny

one refugium could easily attect both. The first pnase of the recovery plan is to maintain and improve conditions in the existing refuyia. Uelisting can occur when five populations of Owens puptisn, each with a minimum overwinteriny population of 500, have become established in five separate areas and nave remained tree from threats

for at least five consecutive years with no toreseeaole threats in the future. Thus, at least tnree new retuyia need to ue established.

The interim objective ot this recovery plan is to restore the Owens puptish to tnreatened status. This ob,eutive can be achieved Dy expanding and assuring the preservation of the existiny popuiations, by estaolisning three additional populations elsewnere, and by minimizing threats to retugia. 17

New habitats selected for reintroduction of puptish should represent

as closely as possible the range of habitat types historically

available to pupfish in the Owens Valley. Potential habitats suitable

for reintroduction of Owens pupfish may require removal of exotic

species, modifications to exclude exotics from re-entry, and

enhancement of habitat conditions for pupfish. Modification of these

areas should be long-lasting but as economical as possible. Habitats

modified must be self-sustaining and protected from conflicting uses

such as sportfishing, groundwater depletion, certain grazing

practices, mining, incompatible land use in adjacent areas, or other

practices that could result in water pollution, or

lower groundwater levels.

Upon establisnment of five refugla with a minimum overwintering

population in each refugium of 500 tish, the Owens pupfish can be

considered for reclassification to threatened status. Removal from

the List of Endangered and Threatened Wildlife will be contingent upon

stability of populations and integrity of the habitats over a five

year period. There should De no threats in the foreseeable tuture.

If any retugium habitat has faced any threat or potential threat to

its existance (dewatering, introduction of exotic fish species,

vandalism, natural disasters, changes in land use or any other

man-caused events), the Owens pupfish shall not be considered for

delisting until the threat to the habitat has been eliminated and the

area is properly protected. When all five refugia have survived for

at least a five year period with no threats to the habitats, then the

Owens pupfish could be considered for delisting. 18

Step-aown Outline

Prime Objective. The primary objective of this recovery plan is to

improve the status ot the Owens pupfish to the

point when it can be removea trom the List of

Endangered and Threatened Wildlife. There are

currently three populations in the Owens Valley.

Two of tnese are located in close proximity to

eacn otner in Fisn Slougn anu will be considered

as one population for the purposes of this

discussion, as any event attecting one retugium

coula easily aftect poth. The tirst pnaSe of tne

recovery plan is to maintain ana improve

conaitions in the existing refugia. Delistiny can

occur when five populations of Owens puptish, each

witn a minimum overwintering population of 500,

have become established in five separate areas and

have remained free from threats for at least five

consecutive years with no foreseeable threats in

the future. Thus, at least three new refugia need

to be established.

The interim objective of this recovery plan is to

restore tne Owens pupfish to threatenea status.

Tnis objective can oe achieved by expanding ana

assuring the preservation ot the existing 19

populations, by establishing three additional

populations elsewhere, and by minimizing threats

to refuyia.

1. Preserve and protect existiny Owens puptish populations and their

habitats.

ii. Owens Valley Native Fish Sanctuary and BLM Spring.

111. Manage exotic species.

1111. Eliminate exotic fishes.

1112. Control bullfrogs.

1113. Control crayfish.

1114. Prevent reintroduction of exotic species.

112. Manage habitat.

1121. Prepare management plan.

1122. Control submergent and emergent vegetation.

1123. Maintain dams.

12. Warm Springs Refuyium.

12i. Manage exotic species.

1211. Manage crayfish as required.

1212. Control exotic fishes.

122. Manage habitat.

1221. Control submergent and emergent vegetation.

1222. Maintain dam.

1223. Redesign outflow to prevent clogging.

1224. Install new entrance in fence. 20

2. Establish and protect viable self-sustaining Owens pupfish

populations in suitable new or restored habitats.

21. Establisn River Spring Lakes population.

211. Eliminate exotic fishes.

212. Control exotic species.

213. Manage emergent ana submeryent vegetation.

214. Prepare ana implement management plan.

215. Assure protection of water ana property rights.

216. Introduce Owens pupfish.

22. Select and establish other suitable transplant sites.

221. Evaluate potential sites.

2211. Evaluate water quality.

2212. Evaluate physical habitat.

2213. Evaluate potential biological effects.

2214. Evaluate habitat protection options on

property ownership and water rights.

2215. Evaluate the extent and long-term security

of source aquiter.

222. Prepare site for retugium.

2221. Assure protection of property and water rights.

2222. Prepare and implement management plan.

223. Select transplant stock and introduce Owens pupfish.

3. Monitor extant populations, transplants and habitat conditions.

31. Determine population size.

32. Determine reproductive success.

33. Assess habitat condition. 21

4. Conduct ecological studies of Owens pupfish for application to

management and recovery.

41. Determine habitat requirements.

42. Determine interactions between Owens pupfish and

mosquitofish.

43. Determine suitability of Owens pupfish for mosquito control

within Owens Valley.

5. Enforce laws and regulations protecting Owens puptish and its

habitat.

51. Enforce applicable Federal, State and local ordinances.

52. Review existing regulations and their enforcement and

recommend needed modifications, as appropriate.

6. Encourage public support by providing information of Owens pupfisn

status and recovery plan objectives.

61. Provide public awareness of Owens pupfish through

audio-visual programs and publications.

611. Provide information to press, TV and radio.

612. Prepare and distribute brochure.

613. Prepare appropriate articles for popular and scientific

publications.

62. Install information signs at essential habitat areas under

State, Federal or DWP management. 2 2.

Narrative

1. Preserve and protect existin_g Owens puptisn populations ana their

habitats.

Primary efforts ShOUIU be directed toward securing and maintaining

populations ot Owens pupfish in thc three existing retugia: Owens

Valley Native Fish Sanctuary (OVNFS), BLM Spring, and Warm

Springs. Information gathered from the management of these areas

has already been used to retine the design of structures used to

create and maintain the habitats in the refugia.

11. Owens Valley Native Fish Sanctuary and BLM Spring.

The refugia at OVNFS has two man-made ponds, which provide

extensive shallow areas for pupfish. The BLM Spring Refugium

also consists of spring areas that have been impounded behind

low dams.

Manage exotic species.

Because exotic species compete with and prey on the

Owens pupfish, their removal or control is necessary.

Lliminate exotic fishes.

The lower impoundment in tne OVNFS can be drawn

down, thereby concentrating all fish in a shallow

central channel. Exotic fish can then be

selectively removed. 23

1112. Control bullfrogs.

Similiarly, other exotic species can best be

controlled during low-water conditions.

Bullfrogs are a predator on juvenile and adult

pupfish.

1113. Control crayfish.

Crayfish may need to be controlled by trapping,

seining or chemicals in order to reduce

predation on the pupfish.

1114. Prevent reintroduction of exotic species.

Posting informational signs around the area may

discourage unauthorized exotic fish

introduction. However, fencing between the

outflow and lower impoundment waters may be

required to discourage or inhibit the

unauthorized introductions which are now

possible.

112. Manage habitat.

Because the habitats are, in part, artificially

maintained by dams or otherwise subjected to human

influences, they need to be carefully manayea.

Long-term plans for Fish Slough may result in a

multiagency management scheme for operatiny the entire 24 area as an ecological preserve and Iliterpretive use area. Conflicts may arise with present uses of the area (primarily waterfowl hunt1mg, fishing and certain grazing practices).

In addition to the management activities outlined below, grazing and fishing must be reduced or eliminated in the vicinity of the refugia in order to preserve the Owens pupfish populations. Grazing may eliminate marsh vegetation and cause water pollution.

Fishing near refugia often leads to the introduction of centrarchids, especially largemouth bass, which prey on the pupfish.

1121. Prepare management plan.

A multiagency management plan that emphasizes

the protection and restoration of natural or

semi-natural habitats in Fish Slough should be

developed.

1122. Control submergent and emergent vegetation.

The lower impoundment can be drawn down to

facilitate control of aquatic vegetation. 25

1123. Maintain dams.

Maintenance of dams and outflow structures is

necessary to provide proper water levels. If

outflow structures clog, water levels can rise

until impoundment structures are breached or

bypassed. This can create a route for exotic

species to gain entrance to the refugia.

12. Warm Springs Refugium.

Activities needed at this refugium include managing exotic

species, performing maintenance work on the habitat, and

monitoring the pupfish.

121. Manage exotic species.

Exotic species may need to be controlled or eliminated

to allow for the existence of the Owens pupfish. At

least once in the history of this refuge, the pupfish

population was eliminated by introduction of

mosquitofish and crayfish.

1211. Manage crayfish as required.

Crayfish, once eliminated by chemical treatment,

have reinvaded the refuge and may again need to

be controlled if the population becomes too

dense. See also, task 1221. 26

1212. Control exotic -fishes.

Mosquitofish may have been introduced either by

individuals using the pond for fishing or by the

county mosquito abatement district for vector

control. The outflow below Warm Springs still

contains mosquitofish ano crayrish as well as

Owens pupfish. Control at mosquitofish may be

required when they appear in the reruyium. Inc

local mosquito abatement office will need to be

contacted to prevent reintroduction or

mosquitofish.

122. Manage habitat.

Periodic habitat maintenance will be required to

protect and sustain the Owens pupfish population at

Warm Springs. The Warm Springs Refugium is used by

local people as a bathing area. Warm water and

isolation are the main attractions. This use is

compatible with the refuyium concept; however, problems

arise because of vandalism, littering, and the

possibility of introduction or exotics by people

unaware or uncaring of tne status of the puptisn. The

fence protecting the refugium from cattle nas been

vandalized, probably to make human access easier. This

can also allow cattle access to the refuyium. 27

1221 Control submergent and emergent vegetation.

Cattails ( IAN) and bulrush ( Scirpus) are

present in all areas surrounding the pool except

on the dam face. It will be necessary to

periodically cut back the vegetation to prevent

encroachment into the pool. This may also help

to control the crayfish population.

1222. Maintain dam.

In addition to regular maintenance, a cage-like

structure needs to be designed and installed

over the outflow to prevent vandalism.

1223. Redesign outflow to prevent clogging.

The outflow structure has been clogged by large

rocks taken from the dam facing. This raised

the water level until it overflowed the dam,

threatening its integrity. The outflow

structure should be modified to prevent

clogging.

1224. Install new entrance in fence.

Warm Springs would be better protected if a more

suitable fence were installed with access

through stiles or walk-ways. This would reduce

the occurrence of fence vandalism by individuals 28

seeking access to itlit rtunL. Such an

entrance would facilitate floirritoring of the

refugium, allow access by bathers, and prohibit

access by cattle.

2. Establish and protect viable self-sustaining Owens puptish

populations in suitable new or restored habitats.

Existing refugia are not absolutely safe from potential threats to

their populations. Two of them are within a mile ot one another

and could easily Pe threatened by a common event. Hence, it is

essential that at least three more retugia be estaulisned.

2i. Establish River Spring Lakes population.

River Springs Lakes in Adobe Valley should be suitable as a

refugium for Owens pupfisn. This area is located

approximately 10 miles northwest of Benton (T1N, R30E, Sec.

24; T1N, R3E, Sec. 19). Although outside the Owens Valley,

the site is nearby and was historically devoid of fish. An

assessment would be required to determine the feasibility of

introducing the Owens pupfish outside or its historic range.

Approval to introduce the species outside of its historic

range would be required trom the Director of the Fish and

Wildlife Service. 29

211. Eliminate exotic fishes.

The springs already contain an introduced population of

Amargosa pupfish ( C. nevadensis amargosae) (Miller

1968). This subspecies of Amargosa pupfish is not

threatened in its native range in the Amargosa River

and would have to be eliminated prior to the

introduction of Owens pupfish to prevent hybridization.

212. Control exotic species.

Any other exotic species identified as a potential

threat to Owens pupfish should be eliminated. Proper

precautions should be taken to insure the protection of

native during any treatments.

213. Manage emergent and submergent vegetation.

Control of vegetation should be done simultaneously

with treatment of the spring to remove the exotic

pupfish.

214. Prepare and implement management plan.

A management plan for habitat improvement and

maintenance in relation to land use practices will need

to be developed. The management plan can then be

carried out. 30

215. Assure protection of water and property rights.

The source and ownership of water for these springs

needs to be evaluated. Rights may need to be acquired.

Part of the springs are on private land. Developing a

suitable agreement or conservation easement with the

present landowner could allow the area to be used as a

refugium.

216. Introduce Owens pupfish.

After exotic species have been eliminated and a

management plan has been approved and implemented , the

Owens pupfish should be introduced.

22. Select and establish other suitable transplant sites.

Additional populations of Owens pupfish need to be

established to insure the species perpetuity.

221. Evaluate potential sites.

Several potential sites exist for use as Owens pupfish

refugia. Little Lake, south of Owens Lake (T23S, R38E,

Sec. 17, 18 and 20) is already owned by California

Department of Fish and Game and is within the presumed

historic range of the species. Springs and seeps

around the periphery of Owens Lake could also serve as

refugia. Black Lake, located in Adobe Valley, is

another potential refugium site (T1S, R31E, Sec. 29 and 31

32; and T2S, R31E, Sec. 5), although located outside

the presumed historic range. Antelope Spring (TS,

R31E, Sec 8), also in Adobe Valley, is another

possibility.

2211. Evaluate water quality.

An evaluation of chemical and physical

properties of the water will have to be made

prior to introduction of pupfish.

2212. Evaluate physical habitat.

Physical characteristics of the habitat will

have to be evaluated as to their suitability as

a pupfish refugium.

2213. Evaluate potential biological effects.

The potential impact of pupfish on native

invertebrates needs to be evaluated.

2214. Evaluate habitat protection options on property

ownership and water rights.

Little Lake is owned by California Department of

Fish and Game, however, the ownership of

property and water rights for Black Lake needs

investigation. Agreements with landowners or

their agents may be necessary. 32

2215. Evaluate tne exten't and ioir erm :seturity of

source aquifer.

The physical properties of the 4qu1ler supplying

water to Little Lake and Black IIIke need to be

investigated.

222. Prepare site for refugium.

If various physical and chemical properties of the

habitat appear conducive to establishing a pupfish

population, then plans snould proceed for refugium

development.

2221. Assure protection of property and water

rights:

All plans will insure protection of private

property and water rights.

2222. Prepare and implement management plans.

Each site will be managed by concepts set forth

in a management plan. This plan will address

any necessary habitat modification and

maintenance and will be developed in association

with private landowners and public agencies

responsible tor areas within and around the

refugium. 33

223. Select transplant stock and introduce Owens pupfish.

Pupfish stock for newly developed refugia should be

taken from refugia most similar in water quality

aspects.

3. Monitor extant populations, transplants and habitat conditions.

Each population must be periodically monitored to determine its

status and the success ot the overall recovery effort. Tne

integrity of the habitat must also be monitored. Populations and

habitats should be surveyed twice annually.

31. Determine population size.

Estimates of population size will be one of the primary

indicators of current status. Populations should be censused

early in the spring (for overwintering level) and near the

end of the summer (for peak population size).

32. Determine reproductive success.

The ability of the pupfish to successfully reproduce through

several seasons is necessary for population viability and as

an indicator of success of the transplanted populations.

33. Assess habitat condition.

Habitat must be monitored to determine if any factors exist

that would be harmful to the Owens pupfisn. 34

4. Conduct eculu_gical studies ot Owens puptisn tor application to

management and_r.ecovery.

Tne refugia will provide opportunities to conduct ecological

studies on the pupfisn. Because the Owens pupfish has been

eliminated from so much of its former range, the reduced

populations have provided very limited opportunity to conduct such

studies. Basic aspects of their biology are either unknown or

open to conjecture from studies restricted to fish held in the

laboratory.

41. Determine habitat requirements.

Substrate and vegetation requirements for feeding, spawning,

establishment, and survival ot territories are needed.

42. Determine interactions between uwens p4ptisn ana

mosauitofisn.

Because of apparent simiiiarity in foods and nabitat,

special emphasis should be placed on determining the

interactions between Owens pupfish and mosquitofish.

43. Determine suitability_ot Owens pugish for mosquito control

within Owens Valley.

The suitability of the Owens pupfish as a mosquito control

agent within the Owens Valley needs to be determined. Use of

the Owens puptisn beyond the Owens Valley (i.e., historic

range) should not be considered for purposes of mosquito

control. 35

5 Entorce laws and regulations protecting Owens pupfish and its

habitat.

All laws to protect pupfish and their habitats should be enforced.

Enforcement personnel from all agencies should be given maps

denoting the location and access points to all refugia within

their area of responsibility. Enforcement personnel and all land

managers should also be made aware of the types of activities

detrimental to Owens pupfish and their habitat.

51. Enforce applicable Federal, State and local ordiances.

Provisions of the Act of 1973, as amemded,

and other applicable laws and regulations should be enforced.

52. Review existing regulations and enforcement and recommend

needed modifications, as appropriate.

The adequacy of existing regulations and their enforcement

should be reviewed once every two years. Needed changes

should be recommended to the appropriate agencies.

6. Encourage public support by providing information of Owens puptish

status and recovery plan objectives.

The public needs to be aware of the plight of the Owens puptisn,

the destruction ot habitat that has occurred in the Owens Valley,

the value of the pupfish, and ways that we can perpetuate its

existence. 36

61. Provide public awareness ot Owens puptisn through

aualo-visual programs aria publications.

Public support for the Uwdns puprish may oe gained úy

providing media coverage of events leading to the pupfish's

recovery, as appropriate.

611. Provide information to press, TV and radio.

Press releases snould be well-written, factual, and

designed to educate the public concerning the need to

recover the Owens pupfish.

612. Prepare and distribute brochure.

An informative aria attractive brochure should be

prepared tnat discusses the plight or tne puptish.

cri a brocnure could be distriouted to interested

parties and agencies.

u.L.J. Prepare appropriate articles tor popular and scientific

publications.

Articles for popular magazines should be prepared

describing the plight of the pupfish. Results of

resedrcn and their applicability to the species'

recovery should be made available to the scientific and

lay communities. 37

62. Instali information signs at essential habitat areas under

State, Federal or DWP management.

Information signs need to be installed at all refugia on

public lands. Such posting could serve as a public education

tool and act as a deterrent against vandalism and the

introduction of exotic species. 38

Literature Cited

Barlow, G. w. i96i. Social benavior ut the desert puptish, Lyprinuaon

macularius, in the fiela and in the aquarium. Amer. Midi. Nat.

65.339-359.

Brown, J. H. 1971. The desert puptish. Sci. Amer. L25.104-110.

Bunnell, S. 1970. The . Cry California. 5:2-14.

California Department of Fish ana Game. 1980. At the crossroads

1980: a report on California's endangered and rare fish and

wildlite. State of California, Resources Agency, Sacramento.

147 pp.

Courtois, L. A., and W. Tippets. i979. SUitUS ot the Owens puptisn,

Cyprinodon raalosus (Miiler), in California. California Fish and

Game Inlana Fish Ena. Spec. Proj. Spec. kept.

Crear, D., ana I. Haydock. i971. Laboratory rearing of the desert

pupfisn, Cyprinodon macularius. Fish. Bull. 69:151-156.

Deacon, J. E., G. Kobetich, J. D. Williams, S. Contreras et al.

1979. Fishes of North America endangered, threatened, or of

special concern: 1979. Fisheries (Bull. Am. Fish. Soc.).

4:29-44. 39

Hiscox, K. J. 1978. Cyprinodon radiosus status at Butte Co. Mosquito

Abatement District. California Dept. Fish and Game, Sacramento.

5 PP.

Kennedy, C. H. 1916. A possible enemy of the mosquito. California

Fish and Game. 2:179-182.

McKee, J. E., and H. W. Wolf. 1963. Water quality criteria. 2nd ed.

California State Water Res. Con. Bd. 548 pp.

Miller, R. R. 1943. The status of Cyprinodon macularius and

Cyprinodon nevadensis, two desert fishes of western North

America. Occ. Pap. Mus. Zool. Univ. Michigan. 473:1-25.

Miller, R. R. 1948. The cyprinodont fishes of the Death Valley

system of eastern California and southwestern Nevada. Misc.

Publ. Mus. Zoo]. Univ. Michigan. 68:1-155.

Miller, R. R. 1968. Records of some native freshwater fishes

transplanted into various waters of California, ,

and Nevada. California Fish and Game. 54:170-i79.

Miller, R. R. 1981. Coevolution of deserts and pupfishes

(genus Cyprinodon) in the American Southwest. Pp. 39-94.

In, R. J. Naiman and D. L. Soltz eds. Fishes in North American

deserts. John Wiley and Sons, New York. 40

Miller, R. R., and E. P. Pister. 1971. Management of the Owens

pupfish, Cyprinodon radiosus, in Mono County, California. Trans.

Amer. Fish. Soc. 100:502-509.

Moyle, P. B. 1976. Inland fishes of California. Univ. California

Press. Berkeley. 405 pp.

Soltz, D. L., and R. J. Naiman. 1978. The natural history of native

fishes in the Death Valley System. Nat. Hist. Mus. Los Angeles

Co. Sci. Ser. 30:1-76. 41

PART III. IMPLEMENTATION SCHEDULE

Table I, which follows, is a summary of scheduled actions and costs for the Owens pupfish recovery program. It is a guide to meet the objectives of the Recovery Plan for the Owens Pupfish, Cyprinodon radiosus, as elaoorated upon in Part II, Narrative section. This table indicates the priority in scheduling tasks to meet the objectives, which agencies are responsible to perform tasks, a time table for accomplishing these tasks, and lastly, the estimated costs to accomplish these tasks. Implementing Part III is the action of the recovery plan that, when accomplished, will bring about the recovery of this endangered species. 4FL

GENERAL CATEGORIES FOR IMPLEMENTATION SCHEDULES

Information Gathering - I or R Acquisition - A

I. Population status i. Lease 2. Habitat status 2. Easement j. Habitat requirements 3. Management agreement 4. Management techniques 4. Exchange 5. Taxonomic studies 5. Withdrawal 6. Demographic studies 6. Fee title 7. Propagation 7. Other 8. Migration 9. Predation 10. Competition li. Disease 12. Environmental contaminant 13. Reintroduction 14. Other information

Management - M Other - 0

J.. Propagation 1. Information and 2. Reintroduction education 3. Haoitat maintenance and 2. Law enforcement manipulation J. Regulations 4. Predator and competitor control 4. Administration 5. Depredation control 6. Disease control 7. Other management

RECOVERY ACTION PRIORITIES

I = An action that must be taken to prevent or to prevent the species from declining irreversibly. 2 = An action that must be taken to prevent a significant decline in species populations/habitat quality, or some utner significant negative impact snort of extinction. 3 = All other actions necessary to provide for full recovery of the species. 43

IMPLEMENTATION SCHEDULE Owens Puptish Recovery Plan

Task Responsible Agencies Estimated Costs 1 General Task Task Duration FWS Other (in $1,000s) Category Plan Task Number Priority (Yrs.) Region Program Agencies FYI FY2 FY3 Comments/Notes

M4 Manage exotic species 111 1 Ongoing CDFG* 4 2 2 OA OVNFS and BLM Springj

A3 Prepare management plan 1121 2 1 1 SE 0.5 Ltor OVNFS and BLM Springj BLM* 2.0 CDFG 0.5 DWP 0.5 UC LWRS 0.5

M3 Control submergent and 1122 1 Ongoing BLM* 1 1 1 emergent vegetation Lat OVNFS and BLM Spring]

M3 Maintain dams Lat OVNFS 1123 1 Ongoing BLM* 1 1 1 and BLM Spring]

M4 Manage exotic species 121 1 Ongoing CDFG* 2 Lat Warm Springs Refugium]

M3 Control submergent and 1221 1 Ongoing CDFG* 0.5 0.5 0.5 emergent vegetation DWP 0.5 0.5 0.5 Lat Warm Springs Refugiumj

M3 Maintain dam Lat Warm 1222 1 Ongoing CDFG* 2 1 1 Springs Refugiumj DWP 1

M3 Redesign outflow to 1223 3 1 CDFG* 4 prevent clogging Lat DWP i Warm Springs Refugiumj 44

Task Responsible Agencies Estimated Costs i General Task Task Duration FWS Other (in $1,000s) Category Plan Task Number Priority (Yrs.) Region Program Agencies FYI FY2 FY3 Comments/Notes

M3 Install new entrance in 1224 3 1 CDFG* 1 fence [at Warm Springs Refugiumj

M4 Eliminate exotic fishes 211 3 2 CDFG* 5 2 Lat River Springs Lake.)

M4 Control exotic species 212 3 Continuous CDFG* 1 1 Lat River Springs Lake]

M3 Manage emergent and 213 3 Continuous BLM* I 1 submergent vegetation [at River Springs Lake]

M7 Prepare and implement 214 3 4 CDFG* 3 2 Task concludes in management plan BLM 2 1 FY 5. Lfor River Springs Lake]

A3 Assure protection of 215 3 1 CDFG* 15 water and property rights [at River Springs Lake]

M2 Introduce Owens pupfish 216 3 1 CDFG* Task occurs in FY4. Lat River Springs Lake]

113 Evaluate potential 221 3 4 CDFG* 7 7 7 Task concikide sites FY 4-

M2 Prepare site for 222 3 3 CDFG* 15 15 Task konciudes in refugium BLM 2 3 FY 4:

41, 45

Task Responsible Agencies Estimated Costs' General Task Task Duration FWS Other (in $1,000's) Category Plan Task Number Priority (Yrs,) Region Program Agencies FY1 FY2 FY3 Comments/Notes

M2 Select transplant stock 223 3 1 CDFG* and introduce Owens pupfish

Ii Monitor extant 3 3 Ongoing CDFG* 5 6 6 populations, transplants BLM 2 2 2 and habitat conditions

13 Determine habitat 41 2 3 CDFG* 15 15 10 requirements BLM 3 3 3 1 SE 3 3

19 Determine interactions 42 2 2 1 SE* 10 5 between Owens pupfish and mosquitofish

19 Determine suitability of 43 3 2 MCP* 5 3 Owens pupfish for mosquito control within Owens Valley

02 Enforce applicable 51 2 Ongoing CDFG* 5 5 5 Federal, State and local BLM 2 2 2 ordinances I LE 1 1

02 Review existing 52 3 Ongoing 1 SE 0.5 Will be done regulations and their CDFG* 0.5 every other year. enforcement and recommend needed modifications, as appropriate 46

1 Task Responsible Agencies Estimated Costs General Task Task Duration FWS Other (in $1,000s) Category Plan Task Number Priority _Ors.) Region Program Agencies FYI FY2 FY3 Comments/Notes

01 Provide information to 611 2 Ongoing CDFG* 5 5 5 press, TV and radio BLM 2 2 2 I SE 1 1 1

01 Prepare and distribute 612 3 5 1 SE* 5 1 Task concludes in brochure FY 6.

01 Prepare appropriate 613 3 Continuous 1 SE* 5 5 articles for popular and scientific publications

01 Install information 62 2 3 CDFG* 5 5 5 signs at essential habitat BLM 2 2 areas under State, Federal DWP 2 2 or DWP management

Key to Responsible Agencies and Definitions

BLM - Bureau of Land Management DWP - Los Angeles Department of Water and Power FWS - U.S. Fish and Wildlife Service (SE = Endangered Species, LE = Law Enforcement) CDFG - California Department of Fish and Game MCP - Mosquito Control Program, Inyo County Environmental Health Department UC LWRS - University of California Land and Water Reserves System Ongoing - tasks currently underway and will continue from year to year Continuous- once funded, tasks will continue year to year

*denotes lead agency

4 47 APPENDIX

List of Agencies Asked to Submit Review Comments

I. California Department of Fish and Game, Sacramento*

2. California Department of Parks and Recreation, Sacramento*

3. Los Angeles Department of Water and Power, Los Angeles*

4. U.S. Bureau of Land Management, Sacramento*

5. National Fishery Research Center, Seattle*

6. U.S. Fish and Wildlife Service, Washington, D.C.*

* Review comments received and addressed in final plan version.