Competitive interactions between invasive and endemic cichlids in Cuatro Ciénegas, México: evidence from stable isotopes and field experiments

Authors: Williamson, CA1, Hendrickson, DA2, Marks, JC1

Year: 2001 (xxxiii)

Abstract

The basin of Cuatro Ciénegas, with over 200 springs and pools, lies in the Chihuahuan Desert of northern Mexico. The area is a high-priority conservation site supporting many endemic fishes and mollusks. Although geographically isolated, the basin’s fauna is threatened by invading species. Stable isotope studies using 13C and 15N revealed dietary overlap between juveniles of the endemic cichlid, Herichthys minckleyi , and the invasive cichlid, Hemichromis guttatus. We conducted a field enclosure experiment to examine this interaction using growth rates as the dependent variable. Results showed H. minckleyi juveniles lost weight in the presence of H. guttatus. In contrast, H. guttatus gained weight in the presence of H. minckleyi, indicating that H. guttatus could out-compete H. minckleyi juveniles. These results provide strong evidence that juvenile H. minckleyi found in habitats with H. guttatus will be negatively affected, potentially leading to increased mortality. [This contribution was supported in part by a grant from The Nature Conservancy to Hendrickson, Marks and Francisco García de León, and made possible by INE permits to García de León.]

Resumen

Interacciones de competencia entre cíclidos invasores y endémicos en Cuatro Ciénegas, México: evidencia a partir de isótopos estables y experimentos de campo En la cuenca de Cuatro Ciénegas, en el Desierto de Chihuahua al norte de México, se encuentran más de 200 manantiales y pozas. Esa área es prioritaria para la conservación ya que alberga a varios peces y moluscos endémicos. A pesar de su aislamiento geográfico, la fauna de la cuenca está amenazada por especies invasoras. En estudios con isótopos estables de 13C y 15N se encontró que existe traslape alimenticio entre juveniles del cíclido endémico Herichthys minckleyi, y el invasor Hemichromis guttatus. Realizamos un experimento de encierro en el campo para analizar dicha interacción, us ando tasas de crecimiento como variable de pendiente. Los resultados indicaron que los juveniles de H. minckleyi pierden peso en presencia de H. guttatus y viceversa. Ello sugiere que H. guttatus compite exitosamente con los juveniles de H. minclkeyi. Estos resultados demuestran que los juveniles de H. minckleyi que cohabitan con H. guttatus serán afectados negativamente, lo cual disminuirá su supervivencia. [Trabajo con apoyo parcial de The Nature Conservancy a Hendrickson, Marks y Francisco García de León, y facilitado mediante permisos del INE a García de León.]

MINUTES OF THE BUSINESS MEETING / MINUTAS DE LA REUNION DE NEGOCIOS President David L. Propst called the 33rd annual business meeting of the Desert Fishes Council to order at 4:15 PM on 16 November 2001 at Sul Ross University in Alpine, Texas. He informed the membership that the minutes of the 2000 Death Valley DFC business meetin g are available in the Proceedings of the Desert Fishes Council Volume XXXII, hard copy of which was available for members to pickup at the registration desk and which is also available in electronic versions via the DFC website. Executive Secretary Phil Pister then provided a financial statement for the Council, prefacing his remarks with the observation that the annual meeting is a poor time to pr ovide exact financial data, because both income from the meeting and related expenses are in a state of flux at that time. However, since the meeting DFC financial status has stabilized and current checking/savings account balance (as of 5 December 2001) is $14,313.52. In addition, the Council retains a Morgan Stanley money market account in the amount of $32,629.81 as of 30 September 2001. Soon to be received from Membership Chair Marsh (now President Marsh) is a check for $20,000.00, about half of which is the W.L. Minckley Memorial Fund. The Minckley Fund will be placed in a separate fund with its annual income being used to fund conservation projects within Cuatro Ciénegas of Coahuila, Mexico. The remainder (unencumbered membership dues income, donations, allocations to the Mexican travel fund, and dollars left in the Pepe Lugo fund) will be added to the existing Morgan Stanley account for future use by the Council. There were 125 DFC members pre-registered for the 33rd annual meeting. In addition, there were several that registered at the meeting. President Propst briefly reviewed the history of the Fossil Creek Renovation Resolution submitted by Jerry Stefferud to the Executive Committee in April 2001. The Executive Committee approved the Resolution and President Propst was to sign and send it to Arizona Game and Fish Department Director Duane Shroufe, Governor of Arizona Jane Hull, U.S. Forest Service Chief, U.S. Fish and Wi ldlife Service Director, and U. S. Bureau of Reclamation Commissioner. The resolution was to urge the responsible agencies to proceed with renovation of Fossil Creek, Arizona, for native fishes. The resolution was mailed in early November 2001. Dean Hendrickson advised the membership that plans for the next annual meeting in San Luis Potosí are progressing. The host for the meeting will be Sr. Juan Miguel Artigas Azas and Sr. Josep Vilet Compeán, both of whom had prior commitments that prevented their attendance at this meeting. Hendrickson explained that they were well along with planning. Commercial flight s now go to San Luis Potosí, so travel there will be much easier than it was last time DFC met in this city. A tentative decision regarding hotel has been made, and if finalized, the meeting will take place entirely in that facility. Visits will be planned to the new zoo and aquarium directed by Sr. Vilet, and a number of interesting potential field trips to desert fishes localities have been suggested by Sr. Artigas. Dates have not been set, but if a potential conflict with the meeting of the Mexican Ichthyological So ciety allows, the DFC meeting will be the week before Thanksgiving-week, as is customary. The local hosts are researching planning details for the SIMAC meeting to coordinate with organizers of that meeting. Additional details regarding the DFC meeting will be communicated by local hosts to DFC Executive Committee in the next month or so. An announcement regarding the San Luis Potosí DFC meeting will be made to the membership some time after 1 January 2002. The call for papers will be made via DFC-L in early summer. Astrid Kodric-Brown, Chairman Best Student Paper Committee, presented the Carl L. Hubbs Best Student Paper Award for the 33rd annual meeting to Heidi Kloeppel for her paper entitled “Interactions of an endemic snail and fish: Negative effects of molluscivore presence on snail density.” President Propst then provided a summary of the Executive Committee 15 November 2001 meeting to the membership. The Executive Committee decided to increase the annual su pport provided to the Translations Committee for Spanish translation of Proceedings of the Desert Fishes Council from $1500 to $2000. Five student travel awards of $200 each will be awarded annually. Students must be members of DFC to qualify and they can only receive award once and must present a paper at the annual meeting. The process for submitting resolutions for consideration was modified to reflect availability of electronic communications. Now, resolutions must be submitted to Executive Committee at least two weeks prior to annual meeting. The Executive Committee will determine if the resolution is appropriate for membership consideration. If deemed appropriate, it will be posted on DFC-L prior to annual meeting. The submitter must bring 150 copies of proposed resolution to annual meeting. Starting with 33rd meeting, PowerPoint presentations ma de at annual meeting will be publishe d in Proceedings unless Editor Dean Hendrickson is requested not to publish.

Under new Council business, the Executive Committee nominated Paul Marsh for next President of the Council. A request for nominations from the floor was made, but no names were offered fo r consideration. Upon receiving no dissention for the Executive Committee’s nomination, Paul Marsh was proclaimed President by acclamation. The Executive Committee recommended to membership that Executive Committee membership be increased by creating an At-Large-Member. This would be an elected position in even years (President elected in odd-years) and individual would serve for two years. The recommendation requires amendments to DFC Constitution and By-Laws. The Executive Committee will draft proposed amendment, post it on DFC-L, and the matter will be voted on at the next annual meeting. A motion supporting this recommenda tion was made by Jim Johnson and seconded by Clark Hubbs. The motion passed without dissention. With Paul Marsh’s election as President, the Membership Chair of Executive Committee was vacated. Volunteers were solicited to fill this vacancy. Kara Hilwig, Matt Ande rsen, Jerry Ste fferud, and Eric Gustafson offered to be considered. The Executive Committee will select among the volunteers and advise membership via DFC-L of their selection. Area Coordinator Committee Chair Nadine Kanim thanked the area coordinators and area report presenters for the excellent presentations made this year. A species status tracking table is being prepared by Area Coordinators and will be displayed at future Council meetings. The list of current Area Coordinators will be updated on DFC-L in early January 2002. Walt Courtenay presented a resolution thanking Sul Ross University and Nathan Allan for helping ensure an excellent meeting. The membership unanimously approved the resolution as follows: Desert Fishes Council Resolution 2001-1 - Thanking the Local Committee: WHEREAS, the Desert Fishes Council, a professional society dedicated to the preservation of North American desert ecosystems, held it 33rd annual meeting at Sul Ross State University in Alpine, Texas; and WHEREAS, Nathan Allan of the U.S. Fish and Wildlife Servi ce in Austin, Texas, served as local host and organizer of that meeting; and WHEREAS, the 33rd annual meeting of the Desert Fishes Council was well organized and well prepared; and WHEREAS, Nathan Allan was unable to attend the meeting due to a family emergency; THEREFORE, BE IT RESOLVED that the Desert Fishes Council thanks Nathan for his efforts in behalf of the Council, and sends best wishes to both him and his family. Passed without dissenting vote, 18 December 2001 Chris Keleher invited DFC members to participate in developing a Scope of Work on biologically defensible recovery goals for endangered species. A final draft report on this effort will be presented at the next meeting of the American Fisheries Society. Pam Hyde presented a resolution relative to the draft population goals for bonytail, humpback chub, Colorado pikeminnow, and razorback sucker in the Colorado River basin developed by Region 6, U.S. Fish and Wildlife Service. Frank Pfeifer provided background information on development of the population goals. After considerable discussion regarding the merits and wording of the proposed resolution, Clark Hubbs made a motion that the business meeting be recessed until 8:00 AM, 17 November 2001 to en able Pam Hyde to reword the resolution to reflect comments made by members during discussion of resolution. There were 27 ayes and 20 nays for the motion of Clark Hubbs. The Business Meeting was recessed at about 5:30 PM. Reconvening of the Business Meeting – 17 November, 2002 President Propst reconvened the business meeting of the De sert Fishes Council at 8:00 a.m. on 17 November at Sul Ross University. Copies of the revised resolution were provided by Pam Hyde to the membership. Points raised during the discussion included lack of familiarity of much of membership with the population goal documents, should a committee be established to review documents; history of DFC is to rely on advice of members that are knowledgeable of issues addressed in resolutions, and concern that the Colorado River Fishes Recovery Team has not been requested to review the final draft of the population goals. Additional changes to the resolution were discussed. After revising the resolution to reflect the suggested changes, it was voted on. The resolution was approved with no dissenting votes as follows: Desert Fishes Council Resolution 2001-2 - relative to draft recovery goals for the bonytail, humpback chub, Colorado pikeminnow, and razorback sucker of the Colorado River basin.

WHEREAS, the draft recovery goals for the four fishes, developed by the U.S. Fish and Wildlife Service, will be integral to the future status of these fish species and the ecosystems upon which they depend; WHEREAS, much biological information has been presented during the development of these goals that indicates that disagreement exists regarding the appropriate approaches and methodologies to be used to develop the demographic and genetic bases for such recovery goals; THEREFORE, BE IT RESOLVED that the Desert Fishes Council, an international society composed of professionals from academic, government, and private organizations and private individuals, at its an nual meeting held in Alpine, Texas, 15 – 18 November 2001, is opposed to the adoption of the draft recovery goals as currently written for the bonytail, humpback chub, Colorado pikeminnow, and razorback sucker of the Colorado River basin; and BE IT FURTHER RESOLVED that the Desert Fishes Coun cil recommends that the U.S. Fish and Wildlife Service redraft the recovery goals based upon the results of a rigorous, independent, scientific review and review of all comments received by the Service; and BE IT FURTHER RESOLVED that copies of this resolution be sent to the Director of the U.S. Fish and Wildlife Service, the Regional Director of Region 6 of the U.S. Fish and Wildlife Serv ice, the Regional Director of Region 2 of the U.S. Fish and Wildlife Servi ce, and the Director of the Upper Colo rado River Endangered Fish Recovery Program prior to the comment period deadline. Passed without dissenting vote, 17 November 2001 The 33rd annual business meeting was adjourned at 9:00 AM on 17 November 2001.

DFC HYDROLOGIC BASIN AND AGENCY REPORT COORDINATORS The following persons coordinated agency and other input to reports presented at this annual meeting. Contact them or authors of those reports for further information.

Oregon (State of) - Rollie White, U.S.F.W.S., Oregon State Office, 2600 S.E. 98th Av enue, Suite 100, Portland, OR 97266, Phone: (503) 231-6179, FAX: (503) 231-6195, Email: rollie_white@fws.gov California (State of) - Steve Parmenter, California Department of Fish and Game, 407 W. Line Street, Bishop, CA 93514, Phone: (760) 872 1171, FAX: (760) 872-1284, Email: spar@dfg.gov Nevada (State of) - Anita Cook, Nevada Department of Wildlife, 1100 Valley Road, Reno, NV 89512, Phone: (775) 688-1532, FAX: (775) 688-1595, Email: acook@ndow.state.nv.us AND Cynthia Martinez, U.S.F.W.S., Southern Nevada Field Office, 1510 N. Decatur Blvd., Las Vegas, NV 89108, Phone (702) 647-5230, FAX: (702) 647-5231, Email: cynthia_t_martinez@fws.gov Bonneville Basin (northern Utah and southern Idaho) - Paul Holden, Bio/West Inc., 1063 West 1400 North, Logan, Utah 84321, Phone: (801) 752-4202, FAX: (801) 752-0507, Email: pholden@bio-west.com Upper Colorado River (upstream of Glen Canyon Dam on Powell Reserv oir, including Green, Gunnison, Dolores, and San Juan Rivers) - Timothy Modde, U.S.F.W.S., Colorado River Fish Project, 266 W. 100 N., Suite 2, Vernal UT 84078, Phone: (435) 789-0354, FAX: (435) 789-4805, Email: tim_modde@fws.gov Lower Colorado River (including Little Colorado, Virgin, Bill Williams, and Gila rivers) - Jerry Stefferud, U.S.F.S, Tonto National Forest, 2324 E. McDowell Road, Phoenix, AZ 85006, Phone: (602) 225-5200 x229, FAX: (602) 225-5295, Email: jstefferud@fs.fed.us Upper/Middle Rio Grande (downstream to the confluence of the Rio Grande and Rio Conchos) - Jim Brooks, U.S.F.W.S., New Mexico Fishery Resources Office, 2 105 Osuna N.E. Albuquerque, New Mexico, 87113, Phone: (505) 346-2538, FAX: (505) 346-2537, Email: jim_brooks@fws.gov Texas (State of) - Gary Garrett, Texas Parks and Wildlife Department, Heart of the Hills Research Station, HC 7, Box 62, Ingram, Texas 78025, Phone: (830) 866-3356, FAX: (830) 866-3549, Email: gpg@ktc.com Northwestern Mexico (including Baja California) - Alejandro Varela-Romero, Universidad de Sonora, DICTUS - Departmento de Investigaciones Científicas y Tecnológicas, A.P. 1819, Hermosillo, Sonora, Mexico, Phone: [011] (52) 62 12 19 95, FAX: [011] (52) 62 12 32 71, E-mail: avarela@guayacan.uson.mx Northeastern Mexico - Salvador Contreras-Balderas, A.P. 504, San Nicolás de los Garza, Nuevo León, Mexico 66450, Phone: [011] (52) (8) 376-2231, Home: [011] (52) (8) 313-1641, E-mail: scontrer@ccr.dsi.uanl.mx

DESERT FISHES COUNCIL MEMBERSHIP Membership is open to any person or organization interested in or engaged in the management, protection, or scientific study of desert fishes, or some related phase of desert fish conservation. Membership is on a calendar year basis (Jan. 1 - Dec. 31) and payment is due in advance. Annual dues s hould not to be confused with meeting registration fees. Members from Latin American countries are not charged dues, but must renew memb ership annually. Additional contributions are solicited to support travel grants to help defray travel costs of students, and deserving professionals, to allow them to make presentations at annual meetings.

APPLICATION FOR MEMBERSHIP Send Completed Form To:

Jerome Stefferud 315 East Medlock Drive Phoenix, AZ 85012 voice: 602-274-5544; email: stefferud@cox.net

Please enroll me in the Desert Fishes Council (DFC) in accordance with the classification I have checked below. I understand that all classes of membership include a subscr iption to the Council’s annual Proceedings. All memberships correspond with a calendar year and are payable in advance. All memberships must be paid in U.S. Dollars, which must be included with the application (personal checks accepted for domestic applications; International Money Orders or International Bank Drafts for foreign applications). Membership dues are waived for members from Latin American countries, but membership must be renewed annually.

Date: _________________________________________________________________ Name: __________________________________________________________________ ______ New or ______ renewal. If renewal, do not complete contact information unless changes are necessary. Address: ________________________________________________________________ __________________________________________________________________ __________________________________________________________________ Voice: ________________ FAX: __________________ e-mail: ___________________ ———–– RATES (U.S. Dollars)———–– ______________ Regular - $25.00 Domestic or Foreign (also see Latin American below) ______________ Student $15.00 (Domestic or Foreign) ______________ Family - $35.00 (2nd Member in Immediate Family; 1 Proceedings) ______________ Sustaining - $35.00 Sustaining ______________ Life Member - $625 ______________ Patron (Companies and Corporations) - $1,000 (Single Payment) ______________ Latin American complementary membership (no charge) ______________ additional donation for DFC travel grants (or specify other use: ____________________________________________________) ______________ TOTAL PAYMENT ENCLOSED (personal checks accepted for domestic applications; International Money Orders or International Bank Drafts for foreign applications).

Meetings, deadlines and other notices and activities of the DFC are announced by e-mail. If you would like to subscribe to the DFC electronic mail list, then send an e-mail cont aining only “subscribe dfc-l firstname lastname” (without quotes and using your own first and last names) to listproc@ lists.cc.utexas.edu. To update an old e-mail address, send an e-mail containing only “unsubscribe dfc-l firstname lastname” from your old address to listproc@lists.cc.utexas.edu and then subscribe from the new e-mail address. We appreciate your attention to updating old addresses!

MEMBRESIA EN EL CONSEJO DE LOS PECES DEL DESIERTO La membresía esta abierta a cualquier persona u organización interesada o involucrada en el manejo, protección, o estudio científico de los peces del desierto, o con alguna tarea relacionada con la conservación de los mismos. Las cuotas de membresía son de un año de cal endario (1 de enero a 31 de diciembre) y deben ser pagados en adelante. No se debe confundir inscripción en congres os con membresía. Para los miembros que viven en países latino americanos, no hay cuotas; la membresía es gratis pero hay que renovarla cada año. Las contribuciones adicionales son bienvenidas y sirven para apoyar becas para los gastos de viaje de los estudiantes y profesionales que lo merezcan, para permitirles hacer presentaciones en los congresos anuales. CONSEJO DE LOS PECES DEL DESIERTO - FORMULARIO DE MEMBRESIA Envíela llena a:

Jerome Stefferud 315 East Medlock Drive Phoenix, AZ 85012 voice: 602-274-5544; email: stefferud@cox.net

Por favor enrólenme en el Consejo de los Peces del Desier to (CPD) de acuerdo con la clasificación que he señalado abajo. Entiendo que todas las clases de membresía incluyen una suscripción a los “Proceedings” anuales del Consejo. Todas las membresías corresponden al año calendario. También, todas las me mbresías deben de ser pagadas en dólares americanos, los cuales deben de incluirse con el formulario de membresía (Se aceptan cheques personales para suscripciones en los Estados Unidos; Para las suscripciones internacionales se aceptan ordenes de pago internacionales o giros bancarios). Fecha: __________________________________________________________________ Nombre: ________________________________________________________________ Membresía _________ nueva o _________ no. (Si no, completa sus datos solo si hay cambios) Dirección: _______________________________________________________________ __________________________________________________________________ __________________________________________________________________ Voz: ________________ FAX: __________________ e-mail: ___________________ ––––– CUOTAS en dólares U.S. ––––– ______________ $25.00 Normal (E.U.A. o Extranjero fuera de países Latino Americanos) ______________ $15.00 Estudiante (E.U.A. o Extranjero fuera de países Latino Americanos) ______________ $35.00 Familiar - $35.00 (Segundo miembro de la familia; 1 “Proceedings”) ______________ $35.00 Soporte ______________ $625 Miembro de por vida ______________ $1,000. Patrocinador (Pago único; Empresas y Corporaciones) ______________ miembro complementario de país latino americano ______________ donativo adicional para becas (u otro uso especificado:____________). ______________ TOTAL (cheques personales de E.U.A. o giros internacionales de otros países.)

Se anuncian los congresos, fechas limites y otras noticias y actividades del CPD por correo electrónico. Para inscribirse a la lista de correo electrónico del CPD, envía un correo con solo el texto “subscribe dfc-l nombre apellido” (sin comillas y usando su propio nombre y apellido) a listproc@lists.cc.utexas.edu. Si cambia su correo electrónico, para actualizar la lista envie un correo desde su dirección vieja a listproc@lists.cc.utexas.edu con solo el texto “unsubscribe dfc-l nombre apellido” y después, inscribirse desde la nueva dirección. Le agradecemos su atención a la actualización de la lista.