DOCSLIB.ORG

Cichlid Species Diversity in Naturally and Anthropogenically Turbid Habitats of Lake Victoria, East Africa

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Cichlid Species Diversity in Naturally and Anthropogenically Turbid Habitats of Lake Victoria, East Africa Aquat Sci (2013) 75:169–183 DOI 10.1007/s00027-012-0265-4 Aquatic Sciences RESEARCH ARTICLE Cichlid species diversity in naturally and anthropogenically turbid habitats of Lake Victoria, East Africa Frans Witte • Ole Seehausen • Jan H. Wanink • Mary A. Kishe-Machumu • Marjolein Rensing • Tijs Goldschmidt Received: 11 October 2011 / Accepted: 10 May 2012 / Published online: 8 June 2012 Ó The Author(s) 2012. This article is published with open access at Springerlink.com Abstract During the past decades, major anthropogenic haplochromines from sub-littoral areas during the pre- environmental changes occurred in Lake Victoria, collapse, collapse and recovery periods. Water over mud including increased predation pressure due to Nile perch is murkier and poorer in oxygen than water over sand, and introduction, and decreases in water transparency and differences in haplochromine communities in these natural dissolved oxygen concentrations due to eutrophication. habitats during the pre-collapse period may predict the This resulted in a collapse of the haplochromine cichlids effects of anthropogenic eutrophication during the col- in the sub-littoral waters of the Mwanza Gulf in lapse and recovery periods. In the pre-collapse period, 1986–1990, followed by a recovery of some species in the haplochromine densities over sand and mud did not differ, 1990s and 2000s, when Nile perch densities declined. but species richness over sand was 1.6 times higher than We studied two data sets: (1) haplochromines from over mud bottoms. Orange- and white-blotched colour sand and mud bottoms in the pre-collapse period; (2) morphs were most common at the shallowest sand station. More specifically, insectivores and mollusc-shellers had higher numbers of species over sand than over mud, whereas for mollusc-crushers no difference was found. F. Witte (&) Á J. H. Wanink Á M. A. Kishe-Machumu Á Laboratory experiments revealed that mollusc shelling was M. Rensing Á T. Goldschmidt more affected by decreased light intensities than mollusc Institute of Biology Leiden, University of Leiden, crushing. During the pre-collapse period, spawning P.O. Box 9505, 2300 RA Leiden, The Netherlands e-mail: [email protected] occurred year-round in shallow areas with hard substrates and relatively clear water. In deeper areas with mud bot- F. Witte toms, spawning mainly occurred during months in which Netherlands Centre for Biodiversity, Naturalis, water clarity was high. No effects of hypoxia on spawning P.O. Box 9517, 2300 RA Leiden, The Netherlands periods were found. It follows that clearer water seems to O. Seehausen support differentiation in feeding techniques as well as Department of Aquatic Ecology and Evolution, year-round spawning, and both may facilitate species Institute of Ecology and Evolution, University of Bern, coexistence. Water clarity is also known to be important Baltzerstrasse 6, 3012 Bern, Switzerland for mate choice. These observations may explain why, O. Seehausen since the decline of Nile perch, haplochromine densities EAWAG Centre for Ecology, Evolution and Biogeochemistry, have recovered, the numbers of hybrids increased and Seestrasse 79, 6047 Kastanienbaum, Switzerland species diversity in the current eutrophic sub-littoral J. H. Wanink waters has remained 70 % lower than before the envi- Koeman en Bijkerk bv, Ecological Research and Consultancy, ronmental changes. P.O. Box 111, 9750 AC Haren, The Netherlands Keywords Dissolved oxygen concentrations Á M. A. Kishe-Machumu Tanzania Fisheries Research Institute, Dar es Salaam Center, Eutrophication Á Haplochromine cichlids Á P.O. Box 78850, Dar es Salaam, Tanzania Light conditions Á Molluscivores Á Spawning periods 123 170 F. Witte et al. Introduction anthropogenic nutrient pollution. Therefore, we analyzed haplochromine catches from littoral sand and mud bottoms In Lake Victoria, more than 500 haplochromine cichlid in Butimba Bay. These catches were made in 1979 and species, 99 % of which are endemic, made up some 80 % of 1980, before the major ecological changes. We compared the bottom dwelling fish mass until the beginning of the differences in densities and species diversity of haplo- 1980s (Greenwood 1974; Kudhongania and Cordone 1974; chromines between these stations, with the differences in Witte et al. 2007a). During the 1980s, the majority of the densities and diversity before and after the environmental haplochromine species in the sub-littoral (6–20 m deep) and changes in the sub-littoral waters of the Mwanza Gulf. offshore areas disappeared (Ogutu-Ohwayo 1990; Witte et al. 1992). This disappearance coincided with the upsurge of the introduced predator, Nile perch, Lates niloticus (L.) Methods (Goudswaard et al. 2008), and with strong eutrophication of the lake. The latter resulted in increased algal blooms and Study period and areas decreases in both water transparency and dissolved oxygen concentrations (Kaufman 1992; Hecky et al. 1994; See- In the present study, three periods are recognized: pre-col- hausen et al. 1997a; Wanink et al. 2001). The process of lapse (1973–1984), collapse (1986–1990), recovery eutrophication had already started decades earlier, with the (2001–2006) (Table 1). The division in these three periods is strong growth of human populations along the lake’s shores based on the following observations in the Mwanza Gulf: (1) (Verschuren et al. 2002; Hecky et al. 2010). Disruption of dominance by weight, and great diversity, of haplochromine the original food web and increased deforestation for Nile cichlids in bottom trawl catches in sub-littoral waters of the perch smoking, may have additionally contributed to Mwanza Gulf until 1984 (Witte et al. 1992); (2) the almost eutrophication and algal blooms. Beginning in the first half complete collapse of the haplochromine populations in sub- of the 1990s, after the decline of Nile perch probably as a littoral waters of the Mwanza Gulf (except for those in rocky result of over-fishing (Matsuishi et al. 2006; Kayanda et al. areas with clear water) in the period between 1986 and 1990 2009; Witte et al. 2009), a resurgence of some haplochro- (Witte et al. 1992; Seehausen et al. 1997a), together with mine species was observed (Seehausen et al. 1997b; Witte algal blooms, and low DO concentrations and Secchi values et al. 2007a, b). However, the initial diversity of haplo- since 1986 (Wanink et al. 2001; Witte et al. 2005); (3) chromines has not fully recovered. recovery of some haplochromine species in sub-littoral During the past years, a lively debate has been ongoing waters since the 1990s (Witte et al. 2007b). regarding impacts of Nile perch predation, over-fishing and The main study area comprised ten sampling stations (A eutrophication on the diversity and abundance of haplo- to J) across the Mwanza Gulf (Fig. 1). Stations A to D with chromine cichlid species in Lake Victoria. It appears that approximately the same length (each about 150 m) are over-fishing may have had a negative impact on haplo- located in Butimba Bay, which has a size of less than chromines locally, but this is unlikely to be a major driver 0.5 km2 (Fig. 1). Stations A and B have sand bottoms, of the lake-wide loss of cichlid diversity (Witte et al. stations C and D mud bottoms. The depth range of stations 2007b). Discriminating between the effects of Nile perch A and C is 2–4 m; that of stations B and D 4–6 m. The sub- predation and eutrophication is more difficult, as they littoral stations E to J with mud bottoms and depths ranging occurred in the same period (Seehausen et al. 1997a; from 7 to 14 m were pooled in the present study and further Verschuren et al. 2002; Witte et al. 2007a, b; Kolding et al. referred to as stations E–J. 2008; Hecky et al. 2010). Moreover, there are two major aspects of eutrophication that may affect haplochromine Environmental parameters communities: decreases in water transparency and decrea- ses in dissolved oxygen (DO) concentrations. As the original study in the pre-collapse period was not Before the environmental changes in the lake, we sam- aimed at relating species diversity with environmental pled relatively pristine sand and mud habitats that differed parameters, the latter were only collected occasionally in light conditions and in DO concentrations close to the (Table 1). To establish the distribution of sand and mud sediment. Mud bottoms are covered with a thick layer of bottoms in Butimba Bay, substrate samples were collected organic debris that easily stirs up, making the water near with an Ekman dredge (Wildlife Supply Company, model the sediment hypoxic and murky. Thus, comparison of 196). A van Dorn water sampler was used to get an densities and species richness of haplochromine cichlids in impression of the thickness of the flocculent mud layer. pristine sand and mud stations offers a unique possibility to Secchi measurements at stations A to D were made in identify potential impacts of decreased water transparency March and April 1980 (pre-collapse period) and in Feb- and DO concentrations that result from lake-wide ruary and April 2002 (recovery period). In the latter period 123 Cichlid species diversity in turbid habitats 171 Table 1 Summary of data sets and their use in the present study Area Data Month and year Period Aim Butimba Bay Comparing species diversity over Station A–D, undisturbed sand and mud 2–6 m bottoms Secchi values March; Apr 1980 Pre-collapse Differences over sand/mud Febr; Apr 2002 Recovery Differences over sand/mud Light (Lux) Febr; Apr 2002, March 2006 Recovery Differences
Load more

Recommended publications
  • View/Download
    CICHLIFORMES: Cichlidae (part 3) · 1 The ETYFish Project © Christopher Scharpf and Kenneth J. Lazara COMMENTS: v. 6.0 - 30 April 2021 Order CICHLIFORMES (part 3 of 8) Family CICHLIDAE Cichlids (part 3 of 7) Subfamily Pseudocrenilabrinae African Cichlids (Haplochromis through Konia) Haplochromis Hilgendorf 1888 haplo-, simple, proposed as a subgenus of Chromis with unnotched teeth (i.e., flattened and obliquely truncated teeth of H. obliquidens); Chromis, a name dating to Aristotle, possibly derived from chroemo (to neigh), referring to a drum (Sciaenidae) and its ability to make noise, later expanded to embrace cichlids, damselfishes, dottybacks and wrasses (all perch-like fishes once thought to be related), then beginning to be used in the names of African cichlid genera following Chromis (now Oreochromis) mossambicus Peters 1852 Haplochromis acidens Greenwood 1967 acies, sharp edge or point; dens, teeth, referring to its sharp, needle-like teeth Haplochromis adolphifrederici (Boulenger 1914) in honor explorer Adolf Friederich (1873-1969), Duke of Mecklenburg, leader of the Deutsche Zentral-Afrika Expedition (1907-1908), during which type was collected Haplochromis aelocephalus Greenwood 1959 aiolos, shifting, changing, variable; cephalus, head, referring to wide range of variation in head shape Haplochromis aeneocolor Greenwood 1973 aeneus, brazen, referring to “brassy appearance” or coloration of adult males, a possible double entendre (per Erwin Schraml) referring to both “dull bronze” color exhibited by some specimens and to what
    [Show full text]
  • Breeding of African Cichlids Facility: Aquatic Animal Research Laboratory (AARL) Rooms 1-2
    Powder SOP BR-02-02 Page 1 of 4 Effective Date: 06-05-2018 Title: Breeding of African cichlids Facility: Aquatic Animal Research Laboratory (AARL) Rooms 1-2 Author(s): Date: 06-05-2018 Kara E. Powder Principle Investigator AARL Facility Date: __________ Manager: John A. Smink Attending Date: __________ Veterinarian: Dr. John Parrish 1.0 OBJECTIVE This SOP describes husbandry, embryo collection, and embryo housing for Lake Malawi cichlids. 2.0 HEALTH AND SAFETY All personnel will be enrolled in the Clemson University Medical Surveillance Program. Attire appropriate to the task must be worn at all times. 3.0 PERSONNEL/TRAINING/RESPONSIBILITIES All personnel must have completed the required Animal Care and Use Committee on-line training. Thereafter, any Clemson employee familiar with the techniques and trained in this and referenced SOPs may perform this procedure. Prior to being assigned full responsibility for performing this procedure, personnel must have demonstrated proficiency in the use of the technique in a closely supervised environment. Documentation of training should be kept for each person performing the procedure. 4.0 REQUIRED AND RECOMMENDED MATERIALS 4.1 Required Materials net, collection dish (roughly 4L), transfer pipette, petri dishes, permanent markers for labeling of dishes, 250 mL flask, 3L tanks, 70% ethanol. 5.0 GUIDELINES The following procedures were developed to meet or exceed the National Institute of Health (NIH) Guide for the Care and Use of Laboratory Animals. 6.0 PROCEDURE 6.1 Tank environment, cichlid mating, and identification of holding females Powder SOP BR-02-02 Page 2 of 4 Effective Date: 06-05-2018 Cichlid breeding groups consist of a single male with several females (generally 15-20 animals with a male:female ratio of 1:4-6).
    [Show full text]
  • Les Haplochromis Spp. (Teleoster, Cichlidae) Des Zones Rocheuses Du Mwanza Gulf, Lac Victoria, Tanzanie : Structure Des Communautés Et Écomorphologie
    Thèses documen ts microfichés Les Haplochromis spp. (Teleoster, Cichlidae) des zones rocheuses du Mwanza Gulf, lac Victoria, Tanzanie : Structure des communautés et écomorphologie. llllnllllnlniinliiiiniiniiliniiniiniliiiliillilillilFonds Documentaire ORSTOM 010012512 no157 3 microfiches Thèses et documents microfichés Orstom, l’Institut français de recherche scientifique pour le développement en coopération La loi du ler juillet 1992 (code de la propriété intellectuelle, première partie) n’autorisant, aux termes des alinéas 2 et 3 de l’article L. 122-5, d’une part, que les « copies ou reproductions stricte- ment réservées à l’usage du copiste et non destinées à une utilisation collective » et, d’autre part, que les analyses et les courtes citations dans le but d’exemple et d’illustration, « toute représentation ou reproduction intégrale ou partielle faite sans le consentement de l’auteur ou de ses ayants droit ou ayants cause, est illicite » (alinéa ler de l’article L. 122-4). Cette représentation ou reproduction, par quelque procédé que ce soit, constituerait donc une contrefaçon passible des peines prévues au titre III de la loi précitée. 0 ORSTOM éditions 1996, Paris ISSN : 0767-922X ISBN : 2-7099-I 342-9 Les Haplochromis spp. (Teleostei, Cichlidae) des zones rocheuses du Mwanza Gulf, lac Victoria, Tanzanie : structure des communautés et écomorphologie Mots clé Haplochromis, Cichlidae, lac Victoria, Mwanza Gulf, zones rocheuses, structure des communaut&s, ècomorphologie, plasticit6 phbnotypique. spkiation. Résumé L’ichtyofaune du lac Victoria est principalement composee d’especes endemiques de Tel6osteer-u appartenant & la famille des Cichlides. La diversite des formes, Observ&e chez ces poissons, en fait ur des exemples les plus remarquables de radiation adaptative chez les vertebres.
    [Show full text]
  • 1990 Volume 23 No. 1
    DRUM & CROAKER f\4 Drum & Croaker Summer 1990 Volume 23, No. 1 DRUM & CROAKER SUMMER 1990 -VOLUME 22, No. 4 Aquarium Nets Sturgeon DRUM & CROAKER (From Sun Herald, Biloxi,MS July 29,1990.) a publication for and by The J. L. Scott Marine Education Center and Aquarium--just call it "the aquarium at public aquariums. Point Cadet"--has landed a coup. The facility now boasts a new exhibit Gulf of Mexico sturgeon, a prehistoric fish that is an endangered species in Mississippi. Issues are published quarterly. "Our aquarium was chosen as the first facility to display the laboratory-reared Gulf Subscriptions: $7.50/ Volume sturgeon raised by the U.S. Fish and Wildlife Service because they liked our aquar­ Two complimentary issues ium and thought public awareness of this species would be enhanced by display in a of every volume are well-visited aquarium," said Dr. Adrian Lawler, aquarium supervisor. provided to recognized public aquariums. The young fish donated are about six inches long, but some have grown to a maxi­ mum of 14 inches. Sturgeons have inhabited Gulf waters from Florida to the Mississippi river for about 300 million years, researchers say. The fish is covered PUBLISHED BY with shields and plates, making it look more like a dinosaur than a fish. The Staff of Fishnet WITH GRANTS FROM An Amelanistic Loggerhead Acquired Aqua vet, Div. of Novalek, Inc. by Jerry Corcoran (CIS ID 76066,500) and AquaScience Research Group, Inc. The newest addition to the GCRL's J.L. Scott Marine Education Center and Aquar­ ium is a sea turtle from the Sandy creek Nature Center (SCNC) in Athens, Ga.
    [Show full text]
  • Taxonomy, Ecology and Fishery of Lake Victoria Haplochromine Trophic Groups
    Taxonomy, ecology and fishery of Lake Victoria haplochromine trophic groups F. Witte & M.J.R van Oijen Witte, F. & M.J.P. van Oijen. Taxonomy, ecology and fishery of Lake Victoria haplochromine trophic groups. Zool. Verh. Leiden 262, 15.xi.1990: 1-47, figs. 1-16, tables 1-6.— ISSN 0024-1652. Based on ecological and morphological features, the 300 or more haplochromine cichlid species of Lake Victoria are classified into fifteen (sub)trophic groups. A key to the trophic groups, mainly based on external morphological characters, is presented. Of each trophic group a description is given com- prising data on taxonomy, ecology and fishery. As far as possible data from the period before the Nile perch upsurge and from the present situation are compared. A list of described species classified into trophic groups is added. Key words: ecology; fishery; Haplochromis; haplochromine cichlids; key; Lake Victoria; taxonomy; trophic groups. F. Witte, Research Group in Ecological Morphology, Zoologisch Laboratorium, Rijksuniversiteit Leiden, Postbus 9516, 2300 RA Leiden, The Netherlands. M.J.P. van Oijen, Nationaal Natuurhistorisch Museum (Rijksmuseum van Natuurlijke Historie), Postbus 9517, 2300 RA Leiden, The Netherlands. Contents Introduction 4 Material, techniques and definitions 5 Lake Victoria haplochromine cichlids in general 6 Key to the trophic groups 11 Description of the trophic groups 12 Detritivores/phytoplanktivores 12 Phytoplanktivores 14 Algae grazers 15 A. Epilithic algae grazers 15 B. Epiphytic algae grazers 17 Plant-eaters 18 Molluscivores 19 A. Pharyngeal crushers 20 B. Oral shellers/crushers 22 Zooplanktivores 24 Insectivores 27 Prawn-eaters 29 Crab-eaters 31 Piscivores s.l 32 A.
    [Show full text]
  • The Molecular Evolution of Rhodopsin in Marine-Derived
    THE MOLECULAR EVOLUTION OF RHODOPSIN IN MARINE-DERIVED AND OTHER FRESHWATER FISHES by Alexander Van Nynatten A thesis submitted in conformity with the requirements for the degree of Doctor of Philosophy Department of Cell and Systems Biology University of Toronto © Copyright by Alexander Van Nynatten (2019) THE MOLECULAR EVOLUTION OF RHODOPSIN IN MARINE-DERIVED AND OTHER FRESHWATER FISHES A thesis submitted in conformity with the requirements for the degree of Doctor of Philosophy Department of Cell and Systems Biology University of Toronto © Copyright by Alexander Van Nynatten (2019) ABSTRACT Visual system evolution can be influenced by the spectral properties of light available in the environment. Variation in the dim-light specialized visual pigment rhodopsin is thought to result in functional shifts that optimize its sensitivity in relation to ambient spectral environments. Marine and freshwater environments have been shown to be characterized by different spectral properties and might be expected to place the spectral sensitivity of rhodopsin under different selection pressures. In Chapter two, I show that the rate ratio of non- synonymous to synonymous substitutions is significantly elevated in the rhodopsin gene of a South American clade of freshwater anchovies with marine ancestry. This signature of positive selection is not observed in the rhodopsin gene of the marine sister clade or in non-visual genes. ii In Chapter three I functionally characterize the effects of positively selected substitutions occurring on another independent invasion of freshwater made by ancestrally marine croakers. In vitro spectroscopic assays on ancestrally resurrected rhodopsin pigments reveal a red-shift in peak spectral sensitivity along the transitional branch, consistent with the wavelengths of light illuminating freshwater environments.
    [Show full text]
  • The Cichlid Fish Oreochromis (Alcolapia) Alcalica
    Journal of Developmental Biology Article Exploring the Expression of Cardiac Regulators in a Vertebrate Extremophile: The Cichlid Fish Oreochromis (Alcolapia) alcalica Gemma Sutton 1 , Lewis J. White 1 , Antonia G.P. Ford 2 , Asilatu Shechonge 3 , Julia J. Day 4, Kanchon K. Dasmahapatra 1 and Mary E. Pownall 1,* 1 Biology Department, University of York, York YO10 5DD, UK; [email protected] (G.S.); [email protected] (L.J.W.); [email protected] (K.K.D.) 2 Department of Life Sciences, Centre for Research in Ecology, Whitelands College, University of Roehampton, Holybourne Avenue, London SW15 4JD, UK; [email protected] 3 Tanzania Fisheries Research Institute, P.O.BOX 98 Kyela, Mbeya, Tanzania; [email protected] 4 Department of Genetics, Evolution and Environment, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK; [email protected] * Correspondence: [email protected]; Tel.: +44-1904-328692 Received: 2 September 2020; Accepted: 30 September 2020; Published: 4 October 2020 Abstract: Although it is widely accepted that the cellular and molecular mechanisms of vertebrate cardiac development are evolutionarily conserved, this is on the basis of data from only a few model organisms suited to laboratory studies. Here, we investigate gene expression during cardiac development in the extremophile, non-model fish species, Oreochromis (Alcolapia) alcalica. We first characterise the early development of O. alcalica and observe extensive vascularisation across the yolk prior to hatching. We further investigate heart development by identifying and cloning O. alcalica orthologues of conserved cardiac transcription factors gata4, tbx5, and mef2c for analysis by in situ hybridisation.
    [Show full text]
  • Seven New Species of Detritivorous and Phytoplanktivorous Haplochromines from Lake Victoria
    Seven new species of detritivorous and phytoplanktivorous haplochromines from Lake Victoria M.P. de Zeeuw, M. Mietes, P. Niemantsverdriet, S. ter Huurne & F. Witte Zeeuw, M.P. de, M. Mietes, P. Niemantsverdriet, S. ter Huurne & F. Witte. Seven new species of detri- tivorous and phytoplanktivorous haplochromines from Lake Victoria. Zool. Med. Leiden 84 (9), 15.x.2010: 201-250, figs 1-23, tables 1-7.― ISSN 0024-0672. M.P. de Zeeuw, Netherlands Centre for Biodiversity, Naturalis, PO Box 9517, 2300 RA Leiden, The Netherlands ([email protected]). M. Mietes, Institute of Biology Leiden, PO Box 9505, 2300 RA Leiden, The Netherlands. P. Niemantsverdriet, Institute of Biology Leiden, PO Box 9505, 2300 RA Leiden, The Netherlands / Rot- terdam Zoo, PO Box 532, 3000 AM Rotterdam, The Netherlands ([email protected]). S. ter Huurne, Institute of Biology Leiden, PO Box 9505, 2300 RA Leiden, The Netherlands. F. Witte, Netherlands Centre for Biodiversity, Naturalis, PO Box 9517, 2300 RA Leiden, The Netherlands / Institute of Biology Leiden, PO Box 9505, 2300 RA Leiden, The Netherlands ([email protected] univ.nl). Correspondence to last author. Key words: Cichlidae; detritivores; East Africa; Haplochromis; phytoplanktivores. Seven new species of haplochromine cichlids from Lake Victoria are described. They comprise four detritivorous and three phytoplanktivorous species. Their affinities to other Lake Victoria haplo- chromines are discussed. Introduction The haplochromine cichlids of Lake Victoria can be classified into several trophic groups according to their diet (Greenwood, 1974; Witte & van Oijen, 1990). Two com- mon groups are the detritivores, mainly feeding on bottom debris, often mixed with phytoplankton, and the phytoplanktivores for which phytoplankton is the major food source (Greenwood, 1974; Witte, 1981; Goldschmidt et al., 1993).
    [Show full text]
  • Dealing with Food and Eggs in Mouthbrooding Cichlids: Structural and Functional Trade-Offs in Fitness Related Traits
    Dealing with Food and Eggs in Mouthbrooding Cichlids: Structural and Functional Trade-Offs in Fitness Related Traits Tim tkint1*, Erik Verheyen2,3, Barbara De Kegel1, Philippe Helsen2,3, Dominique Adriaens1 1 Department of Biology, Research Group Evolutionary Morphology of Vertebrates, Ghent University, Ghent, Belgium, 2 Vertebrate Department, Royal Belgian Institute of Natural Sciences, Brussels, Belgium, 3 Department of Biology, Research Group Evolutionary Ecology, University of Antwerp, Antwerpen, Belgium Abstract Background: As in any vertebrate, heads of fishes are densely packed with functions. These functions often impose conflicting mechanical demands resulting in trade-offs in the species-specific phenotype. When phenotypical traits are linked to gender-specific parental behavior, we expect sexual differences in these trade-offs. This study aims to use mouthbrooding cichlids as an example to test hypotheses on evolutionary trade-offs between intricately linked traits that affect different aspects of fitness. We focused on the oral apparatus, which is not only equipped with features used to feed and breathe, but is also used for the incubation of eggs. We used this approach to study mouthbrooding as part of an integrated functional system with diverging performance requirements and to explore gender-specific selective environments within a species. Methodology/Principal Findings: Because cichlids are morphologically very diverse, we hypothesize that the implications of the added constraint of mouthbrooding will primarily depend on the dominant mode of feeding of the studied species. To test this, we compared the trade-off for two maternal mouthbrooding cichlid species: a ‘‘suction feeder’’ (Haplochromis piceatus) and a ‘‘biter’’ (H. fischeri). The comparison of morphology and performance of both species revealed clear interspecific and intersex differences.
    [Show full text]
  • Endangered Fish Species of the World–A Review
    AACL BIOFLUX Aquaculture, Aquarium, Conservation & Legislation International Journal of the Bioflux Society Endangered fish species of the world – a review 1,2Radu Hărșan, 1,3,4I. Valentin Petrescu-Mag 1 Department of Aquaculture, Faculty of Animal Husbandry, University of Agricultural Sciences and Veterinary Medicine, Cluj-Napoca, Romania, EU; 2 Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine, Cluj-Napoca, Romania, EU; 3 SC Bioflux SRL, Cluj-Napoca, Romania, EU; 4 SC 3M AGC SRL, Cluj- Napoca, Romania, EU. Corresponding author: R. Hărșan, [email protected] Abstract. The present paper summarizes a large part of the endangered and critically endangered fish species of the world. The list was constructed using the comprehensive IUCN Red List of Threatened Species (available in December 2008) and the well elaborated FISHBASE (available on the official website, in 2008) for taxonomy and accepted scientific names of the species. To these two important sources, many scientific papers and communications were added when recent and useful reports were found. However, there is a long way from the fish species list of this review to the world’s complete list of endangered and critically endangered fish species. In our list were not included subspecies, populations, varieties, or species having a debatable taxonomic status. The scope of this review was not to inventorize all the fishes included in these two categories, but to make possible drawing some general conclusions regarding most important possible causes of fish species extinction and to make suggestions concerning fish species conservation possibilities through aquaculture. Key Words: endangered fish species, critically endangered, causes, population trend.
    [Show full text]
  • Bayesian Node Dating Based on Probabilities of Fossil Sampling Supports Trans-Atlantic Dispersal of Cichlid Fishes
    Supporting Information Bayesian Node Dating based on Probabilities of Fossil Sampling Supports Trans-Atlantic Dispersal of Cichlid Fishes Michael Matschiner,1,2y Zuzana Musilov´a,2,3 Julia M. I. Barth,1 Zuzana Starostov´a,3 Walter Salzburger,1,2 Mike Steel,4 and Remco Bouckaert5,6y Addresses: 1Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biosciences, University of Oslo, Oslo, Norway 2Zoological Institute, University of Basel, Basel, Switzerland 3Department of Zoology, Faculty of Science, Charles University in Prague, Prague, Czech Republic 4Department of Mathematics and Statistics, University of Canterbury, Christchurch, New Zealand 5Department of Computer Science, University of Auckland, Auckland, New Zealand 6Computational Evolution Group, University of Auckland, Auckland, New Zealand yCorresponding author: E-mail: [email protected], [email protected] 1 Supplementary Text 1 1 Supplementary Text Supplementary Text S1: Sequencing protocols. Mitochondrial genomes of 26 cichlid species were amplified by long-range PCR followed by the 454 pyrosequencing on a GS Roche Junior platform. The primers for long-range PCR were designed specifically in the mitogenomic regions with low interspecific variability. The whole mitogenome of most species was amplified as three fragments using the following primer sets: for the region between position 2 500 bp and 7 300 bp (of mitogenome starting with tRNA-Phe), we used forward primers ZM2500F (5'-ACG ACC TCG ATG TTG GAT CAG GAC ATC C-3'), L2508KAW (Kawaguchi et al. 2001) or S-LA-16SF (Miya & Nishida 2000) and reverse primer ZM7350R (5'-TTA AGG CGT GGT CGT GGA AGT GAA GAA G-3'). The region between 7 300 bp and 12 300 bp was amplified using primers ZM7300F (5'-GCA CAT CCC TCC CAA CTA GGW TTT CAA GAT GC-3') and ZM12300R (5'-TTG CAC CAA GAG TTT TTG GTT CCT AAG ACC-3').
    [Show full text]
  • The Analysis of the Pharyngeal-Sieve Mechanism and the Efficiency of Food Intake in the Bream (Abramis Brama
    The analysis of the pharyngeal-sieve mechanism and the efficiency of food intake in the bream (Abramis brama. Cyprinidae) Coverdesign: Wim Valen _ "•'milium 1 0456 6663 ^1 Promoter: dr. J.W.M. Osse, hoogleraar algemene dierkunde Co-promotoren: dr. E.H.R.R. Lammens, wetenschappelijk onderzoeker bij het Limnologisch Instituut van de Koninklijke Nederlandse Academie van Wetenschappen dr. F.A. Sibbing, universitair hoofddocent algemene dierkunde p^}o8^©^ *w Willem Hoogenboezem THE ANALYSIS OF THE PHARYNGEAL-SIEVE MECHANISM AND THE EFFICIENCY OFFOOD INTAKE IN THEBREAM (Abramis brama.Cypriaidae) Proefschrift ter verkrijging van de graad van doctor in de landbouw- en milieuwetenschappen op gezag van de rector magnificus, dr. H.C. van der Plas, in het openbaar te verdedigen op woensdag 4 december 1991 des namiddags te vier uur in de aula van de Landbouwuniversiteit te Wageningen. VyMl Sn Voor Tineke, Daphne en Remco Het onderzoek dat in dit proefschrift wordt beschreven werd mogelijk gemaakt door een subsidie van NWO/Stichting BION (beleidsproject 437.241 B) aan Prof. Dr. J.W.M. Osse (LUW) en Dr. J. Vijverberg (Limnologisch Instituut, KNAW), werkgroepleiders van de werkgroep Morfologie van Mens en Dier respectievelijk Aquatische Oecologie. Door vertraging van dit project in het eerstejaar werd deze subsidie aangevuld door LUW en KNAW waardoor verlenging met 1jaar mogelijk werd gemaakt. LANDBOU'W'UNIVERSITEIT WACENTNOF.N ^MO?)^ ^5Lf Stellingen 1 De brasem maakt bij het foerageren achtereenvolgens de volgende keuzen: benthisch of pelagisch; "particulate-" of "filter-feeding" en in het laatste geval met of zonder gereduceerde kieuwfilter kanalen (dit proefschrift). 2 De prooi-grootte selectie bij zooplanktivore brasem wordt voor een belangrijk deel bepaald door de "feeding-mode" (Janssen, 1976; dit proefschrift).
    [Show full text]