IN THIS ISSUE Cite asfollows: Bruce Osborne 2012 Inthis issue. Biology andEnvironment: Proceedings of the Royal Irish Academy 112B (3), i-iii; DOI:10.3318/ BIOE.2012.24. CLASSIFYING HEADWATER STREAMS Headwater streams - the smallsprings and tributaries thatsupply waterfrom theupperreaches of the watershed to the mainriverchannel - have oftenbeen overlookedby freshwater biologists. Despite their small sizeandoften ephemeral nature, headwater streams exerta majorinfluence on the biology, chemistry andwaterquality oftherivers that they flow into.Giventhat they canalsoserve as themainpointofentry ofa rangeofpollutants, a solefocus ontherestoration ofdownstream areas is unlikely toprovide a complete solution toproblems associated withanthropogenic influences on river biology.Headwater streams can be influenced by agricultural andforest activities, buttheir associationwitha widevariation ofsoilsandgeological features often precludes a simple classification that canbe usedas thebasisforassessing theeffects of thesehuman-related factors. Callanan et al., in thisissue,report on a typological classification of headwater streams inIreland basedon thepresence ofa range ofmacroinvertebrate communities. Four maingroups ofheadwater streams wereidentified that werecategorised largely inrelation toenvironmental factors. Geology, inparticular, hada major rolein determining thephysico-chemical characteristics ofheadwater streams and theirassociated macroinvertebrate assemblages. Clearly, theidentification ofreference criteria that adequately account for the extremevariationin the biologyand environmental characteristics ofheadwater streams is a major challenge, althoughthisis urgently neededifwe are to adequately accountforthe impactof anthropogenic factors on the water quality ofrivers. GM PLANTS AND BIODIVERSITY The controversy surrounding theintroduction of GM organisms seemsto continueunabatedas recent coverage in themediaofGM potatotrials and claimsof GM-associated cancerformation in ratsclearly demonstrate. Manywould arguethat GM-related modifications in manyof our crop specieswillbe necessary as partof a portfolio of measures essential forthedevelopment of higher yields andnutritionally improved feedstock. While thishasthepotential forsignificant improvements in plantbreeding, thereare concernsthatthe transfer ofgenesfrom theGM modified cropto wildrelatives couldimpact on native biodiversity, withpotentially negative consequences. Formany of our majorcrop speciesthereare significant barriers to themovement ofgenesas there areno closewildrelatives. Of thecropsgrown in Ireland onlyBrassica napus(oilseedrape)wouldappearto havethepotential to cross withwildrelatives, asa numberof relatedspeciesare weeds and often closely associated withcroplands orlanddisturbed throughanthropogenic activity.Collier and Mullins,in thisissue, analyse theevidence that gene transfer can occuramongthe Brassica and related genera andshowthat this islikely tooccur, albeitwithmorelikelihood withan olderused cultivar of Brassica rapa.Theseauthors arguethat although geneflowislikely tooccurbetween crop plants andcropwildrelatives theconsequences may be largelyinsignificant in the absenceof the evolutionary driver - in thiscase herbicide tolerance . In timetheGM trait is likely to be lostas there isno long-term selective advantage inretainingthis particular characteristic. HILL SHEEP AND UPLAND CONSERVATION The presence ofsheepin uplandareasrepresents something of a conundrum in relation to nature conservation. On the one hand theyare often important asa management tool,asgrazing isoften aneffective wayofmaintaining species biodiversity, whileon theotherhandtheycan havenegative impacts through enhanced soilerosion ornutrient additions and/or, ifgrazing istoointense, result in significant reductions inbiodiversity. The fact that sheep farming can be an important sourceof livelihood andis a contributor to regional economiesalsoneedsto be considered. The question is how canwe balancetheseoften conflicting priorities ? Clearly a better understanding ofthetypes of habitats thatcan be affected is important so that guidelines canbe produced that identify where and when grazingcan occur,while minimising the impact onnative biodiversity andecosystem-related processes. Williamsetal., in thisissue,provide a morerefined analysis ofhabitat selection byScottish Blackface sheepthrough theuse ofa novelGPSbased approachusing tracking collars.Habitat prioritisation was clearlyimportant, with acid grassland beingselected morethanwet heathor blanketbog. In some ways this is not so surprising - acidgrasslands wouldlikely provide a betterfood sourcethan heathor blanketbog DOI:10.3318/BIOE.2012.24 Biology andEnvironment: Proceedings oftheRoyalIrish Academy, Vol.112B, No.3,i-iii(2012).©RoyalIrish Academy i Biology and Environment habitats - but thisapproach provides a moredetailed basis for moreeffective management ofsheep grazing thatis likelyto dependon climatic and seasonalfactors thatinfluence vegetation growth andproductivity. In pooryears, forinstance, the greater utilisation of heathland vegetation may occur,withpotentially greater impacts on a more species-rich community thanthatrepresented by acidgrasslands. A CASE OF MISTAKEN IDENTITY? When did you see yourfirst rhinoceros? Most likely, as I did,in someglasscase in a museum, perhapseven the NaturalHistoryMuseum in Dublin?I was alsoluckyenoughsomeyearsago toseea rhinoceros inthewild,probably oneofthe lastremaining individuals in theDinderNational ParkinSudan - a parkdecimated bypoachers and, when I was there,experiencing severedrought. This is a situation thatseems to be reflected globally, withrhinoceros populations continuing todecline atanalarming rateduetoa combination ofhuman-related causesandclimate change.The Javan rhinoceros (Rhinoceros sondaicus ), inparticular, isregarded asa critically endangered species that is notevenwell-represented in museum collections. The extent ofitspresence inmuseum collections is alsofurther...