Museum Teclinical Report No. 45

STATUS SURVEY OF THE PEARL DARTER ( AURORA) IN THE FASCAGOULA RIVER SYSTEM

Henry L. Bart, Jr. and Royal D. Suttkus Department ofBiology Tulane University New Orleans, LA

Funded by U. S. Fish and Wildlife Service Project No. E-1, Segment 10

Mississippi Department ofWildlife, Fisheries, and Parks Museum ofNatural Science 111 N. Jefferson Street Jackson, MS 39201

1996 FINAL PROJECT REPORT

STATE; Project El-1, Segment 10

STUDY TITLE: Status Survey of the Pearl Darter {Percina aurora) in the Pascagoula River System

PRINCIPAL INVESTIGATORS: Henry L. Bart, Jr. and Royal D. Suttkus

PROBLEM AND NEED STATEMENT

The Pearl darter, Percina aurora is a recently described species closely allied to the , Percina copelandi (Suttkus et al. 1994). The species is known only from the

Pearl and Pascagoula river drainages in Louisiana and Mississippi. It has long been the subject of conservation concern because itis uncommon, infrequently collected, andwhen found, usually occurs in low numbers. Deacon et al. (1979) and Williams et al. (1989) assigned the Pearl darter the status of "threatened" due to "present and threatened in Louisiana and Mississippi." Gilbert and Burgess (1980) referred to the species as extremely rare and bordering on extinction. The species does appear to have been eliminated from the Pearl River drainage. The last time pearl darters were collected from that system was August 1973, this despite the fact that one of us (RDS) has been taking any as 64 fish collections per year from middle and lower reaches of the Pearl River since that time in connection with environmental monitoring work.

Collecting efforts in the Pascagoula River drainage have been infrequent in comparison to efforts in the Pearl River drainage. Pascagoula River records of P. aurora in the Tulane Fish collection cover the period August 1958 to April 1987, but represent far fewer lots (10) and specimens (45) than the lot (121) and specimen (544) totals from the Pearl River drainage. Dr.

Stephen T, Ross and students at the University of Southern Mississippi (USM) have collected p. aurora on several occasions since that time. The more recent dates of collection of P. aurora in the Pascagoula River system suggests that species still survives there. However, little else is known about the status of the Pascagoula River population.

STUDY OBJECTIVES

This study was conducted to assess the status of the Pascagoula River population of the

Pearl darter, and to assemble other necessary information for evaluating the Pearl darter for possible federal listing. The objectives were to determine present Pascagoula River system distribution of the species and relate this to the historical distribution; determine critical habitat requirements of the species; and assess adverse man-made or natural impacts on remaining stocks.

METHODS

Records of all previous collections of the Pearl darter in the Pascagoula River drainage were assembled. Specimens in all but two of the lots were examined by us to verify the taxonomic identification. In the other two cases, the identity of specimens was confirmed by ichthyologists at the institutions where the specimens are housed. Sites in the Pascagoula River system where the Pearl darter was previously collected, and other nearby sites, were surveyed to determine the species present distribution and status. Most of the collections were made with small seines, the primary sampling gear used by earlier workers. A backpack electrofisher was used to sample sites with rocky outcrops.

We sampled over substrates that we expected to produce Percina in general and P. aurora in particular. This included shallow gravel riffles and rock outcrops, deep gravelly to sandy channels and pools below shallow riffles. We planned to measure habitat conditions (depth, current, substrate, structure) in the vicinity of all Pearl darter captures. Measurements were to be made at 1 m intervals along five cross-stream transects spaced 1-m apart.

RESXJLTS AND DISCUSSION

Summary of Pascagoula River Drainage Records of Percina auroroai

A total of 45 specimens of P. aurora has been taken from the Pascagoula River Dr. to date. Records for these collections are summarized below bycounty, lot (catalog) number with institutional acronym, number of specimens (in parentheses), location, and date. Institutional acronyms are as follows: NLU = Northeast Lx>uisiana University; TU = Tulane University

Museum of Natural History; USM = University of Southern Mississippi; USNM = United

States National Museum; UT = University of Tennessee.

JACKSON COUNTY: USNM 129182 (6), Pascagoula R. at Dead Lake, collected by Samuel F. Hildebrand, 12 May 19^33. STONE COUNTY: TU 144228 Black Cr. at large loop along right bank, SE Board and Horseshoe lakes (T2S, RlOW, Sec 2), 30 November 1985^ PERRY COUNTY: TU 144698 {1), Black Cr. at Miss Hwy 318 (TIS, RlOW, Sec 34), 4

April 1986, and TU 148420 (3), 24 April 1987. USM 8148 (3), Leaf R., 1.1 mi downstream of Wingate Bridge, 23 October 1989; USM 9137 (1), Leaf R., 2.8 mi below Hwy 29, 7 August ELi- •• •• 1990; USM 9575 (1), LeafR., 4.6 mi above Hwy 29, 2 August 1990: USM 8785 (2), LeafR., 5 mi upstream from Hwy 29, 9 March 1^. COVINGTON COUNTY: USM 6151 (2), Okatoma Cr., 1.2 airmi SSanford, 5October 1979. GEORGE COUNTY: USM 4293 ^),

Pascagoula R., 1.3 mi above Jackson County line, 23June 1988; TU 65841 (3), Pascagoula R.,

\i 6 mi SE Benndale (T3S, R8W, Sec 1), 14 November 1970, and TU 89772 (2), 13 July 1^; TU 100135 (^, Pascagoula R. along right bank opposite Merrill (TIS, R7W, Sec 19), 22

October 1976; TU 100159 (2), Pascagoula R. and lower Leaf River along right bank, 0.5 mi W Merrill (TIS, R7W, Sec 19), 22 October 1^7^ and TU 100202 ^ 29 October 1976. JONES COUNTY: NLU 20547 (^, Leaf R. at mouth of Eastabutchie Branch (T6N, R13W,

Sec 33), 7 October 1971; USM 17286 1/2 km downstream of Eastabutchie Bridge, 17

October 1994 (identity verified by Stephen T. Ross, University of Southern Mississippi).

GREENE COUNTY: USM 4444 (1), Chickasawhay R. at bend about 1.8 mi above Mineral Branch, 6 August 1^88; USM 4242 Chickasawhay R., 3.3 mi above Mineral Branch, 19

June 12SS; USM 4975 (1), Chickasawhay R., 4.6 mi below Hwy 63, 17July 1988. CLARKE

COUNTY: TU 19379 (1), Chickasawhay R. at US Hwy 45, 1 mi S Shubuta (TION, R7W, Sec 10), 21 August 1958. LAUDERDALE COUNTY: TU 121097 (J), Chunky Cr., 4 mi NUS Hwy 11 at Enterprise (T5N, RUE, Sec 36), 18 August 1979; UT 91.2159 (1^ Chunky Cr. at

Interstate Hwy 59, 18 May 1981 (identity verified by David A. Etnier, University of

Tennessee).

Field Survey of sites of previous capture:

A total of 30 collections was made between 18 September and 21 December 1996.

Collections were made at all 19 sites of former capture, and 11 new sites that were either close to sites of previous capture or appeared to offer favorable habitat. Collecting effort was confined to fall and early winter to take advantage of low stream flows and to minimize impact on young and reproductive age fish. Ten of the collections were preserved and are now archived at TU for permanent record. Number of specimens in the lOafeinved collections total 2239. At the other collections sites, fish were identified in the field and released-aljve. Pearl darters were not taken or seen in any of the collections made during this

survey. The most recent collection was a single adult specimen collected from the Leaf River

below Eastabutchie Bridge in October 1994 by students of Dr. Ross of USM.

Except for the omission of the pearl darter, faunal composition does not appear to have

changed much at prior collection sites. Four species of Percina were encountered: the freckled

darter, P. lenticula; the black banded darter, P. nigrofasctata; the dusky darter, P. sciera; and tjje-saddlebackrdarter^ P. vigitrJnThe^ent survey, darters accounted for between 17 and 46 percent of total catch (mean = 31%) at sites with extensive hard substrate (gravel and rocky outcrops), Percina spp. accounted for between 8 and 31 percent of catch (mean = 17%). Darters and Percino. made up much smaller proportions of samples from sites with extensive sand and limited gravel/rock bottom (averaging 5% and 2.5% of catch, respectively). The

percentages are comparable to those recorded in the previous collections. Previous collecting efforts suggest that the pearl darter is extremely rare in the Pascagoula River drainage. Only 19 pearl darters were taken out of 19,300 total fish in the 10 previous TU collections containing the species. This translates to roughly 2 specimens per. collection or 0.01% ofall fish in the 10 collections. Dr. Ross and students at USM provided an estimate of rarity of P. aurora based on total sampling effort in streams in the Pascagoula River drainage known to support the species (data from the "Mississippi Freshwater Fishes database ). Out of379 collections taken since 1974 totalling 81,514 fish specimens (all species) from mainstem portions ofthe Chunky, Leaf, Pascagoula, and Chickasawhay rivers, and Black

and Okatoma creeks (possibly including some coliectfeft^j^m upper reaches of the latter two creeks where the pearl darter likely does not naturally occur), pearTdaftej^s^? in all) were taken in only 10 collections (2.6% of collections). This translates to only one capture of 1.7

specimens in every 38collections (W.T. Slack personal communication). Divided over thetotal number of specimens, only one pearl darter was taken for every 4,795 specimens (0,02% of all specimens taken). This suggest that 30 collections over the span of three months (our effort) is not a sufficient amount of effort to produce specimens of P. aurora. The4au^gestliumber of individuals taken at any one time in the Pascagoula River drainage was six individuals taken by Samuel Hildebrand in the^owerJPascagoulaJEiive in 1933. Four TU collections (3471, 4006, 6049 andJ4J2QX-=»*^-^ USM collection contain three individuals, and one USM collection contains four individuals. The pearl darter was historically more common in the Pearl River drainage than it has been in the Pascagoula River drainage. In 716 TU collections taken prior to 1974 from portions ofthe Pearl River drainage known to support P. aurora, the species was taken in 104 collections (14%). Pearl darters made up 444 of 441,162 specimens in the 716 collections (one in every 994 specimens taken or 0.1% of total catch). The 104 TU collections with pearl darters contained an average of4.3 specimens per collection. An additional 17 collections at Northeast Louisiana University contained a total of 100 pearl darters (5.9 specimens per collection). The overall average number of specimens per collection for Pearl River drainage collections containing the species was 4.5 (544 specimens in 121 total collections). The species tended to be more abundant at the type locality than at other locations. Thirty four collections from the type locality contained an average of six specimens per collection, with numbers for individual

collections reaching as higii 68J^ividuals. Figure 1is a map of the distribution o^^lhe Pascagoula River drainages, showing the last years of collection of the species in areas of former capture. The species disappearance from the Pearl River drainage appears to be tied to events occurring in the late 1960's to early 1970's. Quarterly surveys of numerous sites in the upper and lower Pearl River from that time to the present leave little doubt that the species is now extirpated from that system. Most of the collection sites in the Pascagoula River system are more recent than 1973, the last year the species was collected in Jhe Pearl River drainage. Twelve of the 23 coll^fibhs (52%)^have come from the nine year period from November 1985 to October 1994, and represent areas that have been surveyed more or less regularly since that time. Although P. aurora is very rare in the Pascagoula River drainage, the number of recent

collections suggests that species continues to survive there. By examining specimens in the large sample of Pearl darters from the Pearl River drainage, we have determined that the species spawns in March and April (Suttkus et al. 1994). By June, young-of-year between ranging in size from 24 and 28 mm SL begin to show up in samples. Females that reach 40 mm SL by the following spring are sexually mature with mature ova in their ovaries. Males mature at slightly larger sizes than females (42 mm SL). Most pearl darters mature in one year. Figure 2 is a distribution map showing mean sizes (standard lengths) and numbers of specimens in the sample (in parentheses) for all previous collection localities in both the Pearl and Pascagoula River drainages. In the Pearl River, virtually all of the specimens form the Strong River at the type locality are large, adult-sized specimens probably in their second or

third year of life. Average size decreases downstream in the Pearl River with most specimens being immature, juvenile or subadult (non-reproductive) sizes. ^ ^ It is clear from past collections that the Strong River rapids was an important historical spawning habitat for the pearl darter in the Pearl River system. We still regard the habitat at —Ihat-sdte^s-ideal spawning habitat for the species. Initially, we thought the type locality was the only place specimenrirr^reeding-i::DnditiojL were obtained (Suttkus et al. 1994: p. 17). However, careful reexamination of specimens in March and April collections from upper, middle and lower areas of the Pearl River proper (especially those just below the sill at Pools Bluff) revealed that specimens in reproductive condition were obtained from all of these areas. Thus, the species probably also spawned in other habitats in the main stem ofthe Pearl River. That these areas were less optimum for spawning than the type locality is suggested by the smaller numbers of "reproductive" fish, and the smaller average sizes (and presumably lower reproductive outputs) of these fish. The large number of young and juvenile sized fish taken in the middle Bogue Chitto River suggests that the species historically spawned in the upper reaches

of this tributary as well. Reproductively mature specimens come from four areas of the Pascagoula River drainage: Chunky River north of Enterprise, Okatoma Creek south of Sanford, Leaf River near Eastabutchie, and Black Creek at MS 318. All of these areas should be regarded as possibly supporting reproductive populations. The species has not been collected in Okatoma Creek since 1971. The most recent collection in Chunky River was 1981. The species was last collected in lower Black Creek in 1987. Of the four specimens taken there (all from April), two were immature and two were mature females. The single adult specimen taken from the Leaf River

near Eastabutchie (Oct 1994) was the most recent collection in the Pascagoula River drainage system. Thus, iiMs^^l^ely that this portion of the Leaf River (and possibly also lower Black Creek) continue to support reproduaiig^opulations. Actual spawning sites in the Pascagoula River drainage are unknown. However, at least three ofthe above areas - Okatoma Creek below Collins (Ross et al. 1992), Chunky River above enterprise. Leaf River above Eastabutchie - offer extensive exposed_outcrops of lime and sandstone similar to those found at the type locality In the Strong River. Two additional streams, BogueHomo ^d Thompson creeks (denoted by hollow circles on fig. 1), appear to oilerf^orab^e^i^itat^s well. We failed to collect pearl darters at two sites on these streams, but feel that additional field work is needed.

CONCLUSIONS AND CONSERVATION RECOMMENDATIONS The Pearl darter is extremely rare in the only drainage known to support the species in the most recent times. The species has been collected at a rate of only one specimen per 4,800 individuals since 1974. A1995 field survey of 19 sites known to support the species in the past, and 11 other sites that appeared to offer favorable habitat, failed to produce a single specimen. Specimens at reproductive size are known from four sites, only two of which have produced specimens since 1981, Specimens in reproductive condition (females with mature ova) are known from only one of these sites (lower Black Creek). Sites of actual spawning are unknown in the Pascagoula River drainage. Based on these findings, we feel that protective status of highest category is certainly

warranted for the pearl darter, and that adHitibnaLeffort shotildj^e^^t forth to identify spawning .—sites and^vidence ofreproduction. Where specimens in spawning condition-are found, attempts should be made to observe spawning behavior in the field (e.g., with mask and snorkel). Spawning pairs should also be returned to laboratory aquaria for spawning observations. Any

young spawned and reared in the laboratory could be reintroduced into the wild. As additional information on critical spawning habitat is obtained, a more detailed program of captive

propagation should be implemented. The ^earl darter,_Jikr. the coal darter (Percina brevicauda) and the channel darter {Percinct copclundi)^ favors channels of moderate depth. One reason for the species low representation in past collections may be that the favored habitats are sometimes difficult to sample with seines, the sampling gear used in the vast majority ofthese early collections. One approach to monitoring occurrence in these habitats on a more or less continuous basis is to set minnow traps, baited with dog or cat food, in these areas and check them periodically. This type of passive monitoring program could be implemented immediately on managed game preserves in lower portions of the drainage basin, where state Wildlife and Fisheries personnel would be available to check and re-bait the traps on a regular basis. Because of his close proximity to areas of the Pascagoula River system that have recently supported Pearl darters and his ongoing surveys of these portions of the drainage which have produced most of the recent specimens. Dr. Stephen T. Ross and students from the University of Southern Mississippi should be involved in all future monitoring and recovery plans. For our part, we intend to continue to survey the drainage basin this spring and summer. A student currently working on a Masters of Science degree at Tulane University will use specimens here

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from the Pearl River drainage to work out4mpQi;tan^spects of the species' life history. This information could prove to be beneficial to future recoveryheffbrts. ^ One of us (HLB) would also like to use the extensive time series fish data at TU from the Pearl River drainage in a comprehensive landscape ecology study to determine whether the recent history of land use in the Pearl River drainage basin has contributed to the demise of the Pearl darter and other fish species. The findings could be extended to other aquatic biota as well. Hopefully, lessons learned from the Pearl River drainage will help us to conserve species such as the Pearl darter in the Pascagoula River drainage and other watersheds.

LITERATURE CITED Deacon, J. E., G. Kobetich, J. D. Williams, S. Contreras, and other members of the committee of the Amer. Fish. Soc. 1979. Fishes of North America endangered, threatened, or of special concern: 1979. Fisheries, 4(2): 29-44. Gilbert, C. R. and G. H. Burgess. 1980. Percina copelandi (Jordan), channel darter. Page 721 In: D. S. Lee etal. eds. Atlas ofNorth American freshwater fishes. North Carolina State Mus. Nat. Hist., Raleigh, 854pp. Ross, S. T. and W. M. Brenneman. 1991. Distribution of freshwater fishes in Mississippi Freshwater Fisheries Report No. 108. D-J Project Completion Report F-69. Mississippi Department of Wildlife, Fisheries and Parks. Jackson, MS. 548 pp. Ross, S.T., D.C. Heins, and J.W. Burris. 1992. Fishes of Okatoma Creek, a free-flowing stream in south central Mississippi. Proc. Southeastern Fishes Council No. 26:2-10. Suttkus, R. D. 1985. Identification of the period, loa vigil Hay. Copeia 1985 (l):225-227. Suttkus, R.D., B.A. Thompson, and H.L. Bart, Jr. Two new darters, Percina {Cottogaster)^ from the southeastern United States, with a review of the subgenus. Occasional Papers Tulane University Museum of Natural History No. 4, 46 pp. Williams, J. E., J, E. Johnson, D. A. Hendrickson, S. Contreras-Balderas, J. D. Williams, M. Navarro-Mendoza, D. E. McAllister, and J. E. Deacon. 1989. Fishes of North America endangered, threatened, or ofspecial concern. Fisheries, 1989. 14(6): 2-20.

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MISSISSIPPI

LOUISIANA

Sc*l* 1.-3001000 '0 20 30 40Mile>

90' 89

MISSISSIPPI

43.6 (2)

51.25 (148) 35.5 (1)

40.17 (16)

35.32 (47)

37.5 (3) 36.9 (4)

27.2 (3) 33.3 (17) ?^^^^^44.34 (5) 38.9 (8) ( ) I 32.3 (5) ' M /I 36.98 (137) 26.7 (4)^1 y! 39.9 (6)

LOUISIANA

40 Miles ;#•