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Home , Dipseudopsidae, Ecnomidae, Hydropsychidae, Hydroptilidae, Leptoceridae, Sabie River

A SNAPSHOT IN TIME: FRESHWATER DIVERSITY IN RIVERS OF THE

Holland, A.J. 1, Barber-James, H.M. 1,2 and de Moor, F.C. 1,2 1 Department of Freshwater , Albany Museum, Makhanda (Grahamstown) 6139, 2 Department of Zoology and Entomology, Rhodes University, Makhanda (Grahamstown) 6139, South Africa

[email protected] @africaddis SOME HISTORY

• 1921: earliest record of aquatic pollution in the park • Gold mines near village discharged waste directly into the Sabie River • Early 1930s tourists refused to use Sabie River water for domestic purposes • Hippopotami were starting to get affected and the pollution eventually caused death of livestock • 1933 National Park Board initiated benthic fauna survey in response with the result that “there was virtually no small aquatic life in the Sabie River.” • 1944 legislation was passed preventing the dumping of raw waste directly into the river SOME HISTORY

• 1959: research project ‘South African Hydrobiological Regions’ by Dr AD Harrison and JD Agnew (Hydrobiology Division of the National Institute for Water Research) • Sampled Sabie (impacted) and Crocodile (unimpacted) for comparison Results: • Fauna of the Sabie River far more diverse than that of the Crocodile River, which showed that the Sabie River had recovered • many unrecorded mayflies and caddis flies were found • But the fauna has strong links with that of Central Africa • Material donated to Albany Museum NATIONAL FRESHWATER COLLECTION, ALBANY MUSEUM

• This collection has over 2-million specimens from all over Africa, and is the largest such collection on the continent. • 70% of data connected to each specimen are housed in the database • 1% has been imaged and DNA barcoded WAYS TO USE THE COLLECTION

(1) New distribution records for that have not been recorded previously in the park or at sites previously surveyed, (2) records of species missing in the park that used to be present, (3) discovery of new species previously unknown to science (4) changes in species assemblages reflecting changes in ecological conditions over time. INSECT BIODIVERSITY LOSS TRICHOPTERA – CADDIS FLIES

• Largest aquatic insect • Inhabit many different biotopes from fast flowing rivers to temporal ponds • Sensitive to water chemistry changes - useful group to use for Environmental Impact studies and for determining water quality and environmental health. • The most pollution tolerant species belong to the net spinning family • To identify caddis flies to species level adult males are needed as their genitalia have distinct structures QUICK LIFE-CYCLE

Trichoptera family diversity at entrance (upper) and exit (lower) sites on the Sabie and Crocodile Rivers

Map by Bayanda Sonamzi MATERIAL FROM THE AM COLLECTION

Survey 1 Survey 2 Survey 3 Sampling 1959 July, November 1985 April, September 2015 September 1960 July, November 1986 April, September 2016 April, September 2017 March Season Low- and high-flow Low-flow Low-flow Methods Surber sampler Hand-net (biotic index, SASS, general SASS prototype collection, Light trap method) Biotopes Stones in current Stones in and out of Stones in and out of current, vegetation, current, vegetation, sediment sediment, logs, bedrock, anything of interest Preservation 3% Formalin and 70% 3% Formalin and 70% 80% ethanol ethanol after sorting ethanol after sorting EXPECTATIONS

• Sabie River is more diverse than the Crocodile River • Diversity increases or stays the same over time • Surveys 2 and 3 are comparable, survey 1 is not as methods have not been standardized for all collecting events • Diversity and/or abundance of survey 3 should be much higher than surveys 1 and 2 due to the more comprehensive collecting effort during survey 3 Upper Crocodile River CROCODILE 1400 RIVER 1200 1000 800

• Survey 2 and 3 600 Abundance dominated by 400 Hydropsychidae 200 Hydropsychidae 0 • Survey 2 stable survey 1 survey 2 survey 3 results 1959/60 1985/86 2015/16/17

• Increased Lower Crocodile River abundances indicate 1400 improved sampling 1200 methods over time? 1000 Ecnomidae 800 Philopotamidae 600 Leptoceridae

S1 S2 S3 Abundance 400 Hydroptilidae Upper 4 5 6 200 Hydropsychidae Lower 4 5 5 0 survey 1 survey 2 survey 3 1959/60 1985/86 2015/16/17 Upper Sabie River 1400 SABIE RIVER 1200 1000 Dipseudopsidae 800 Ecnomidae

• Survey 1 at upper 600 Philopotamidae Abundance Sabie only 400 Leptoceridae Hydroptilidae Leptoceridae at 200 Hydropsychidae lower sabie low 0 abundance but high survey 1 survey 2 survey 3 diversity 1959/60 1985/86 2015/16/17 • Surveys 2 and 3 Lower Sabie River diversity and 1400 abundance 1200 increases over time 1000 Dipseudopsidae 800 Ecnomidae 600 Philopotamidae

Sab S1 S2 S3 Abundance 400 Leptoceridae Upper 1 5 6 Hydroptilidae 200 Hydropsychidae Lower 5 5 6 0 survey 1 survey 2 survey 3 1959/60 1985/86 2015/16/17 ADJUSTING RESULTS

• Survey 3 included additional light trapping to catch adults stages (important for caddis fly species identification) • all adults were removed from all surveys to compare larval stage results (including any Restaurant “by-catches” in the older surveys) UpperUpper Crocodile Crocodile River River- adjusted CROCODILE 1400 RIVER 1200 1000 Dipseudopsidae Ecnomidae 800 Ecnomidae Philopotamidae 600 Philopotamidae

• Upper Crocodile lost Leptoceridae Abundance Abundance Leptoceridae Dipseudopsidae 400 Hydroptilidae Hydroptilidae 200 Hydropsychidae • Hydroptilidae and Hydropsychidae 0 Leptoceridae are the survey 1 survey 2 survey 3 only 2 families present 1959/60 1985/86 2015/16/17 at Lower Croc after LowerLower Crocodile Crocodile River River adjusted adjustment 1400 • Diversity and 1200 abundance decreases 1000 Ecnomidae 800 in the recent survey Philopotamidae 600

Leptoceridae

AbundanceAbundance Croc S1 S2 S3 400 Hydroptilidae 200 Hydropsychidae Upper 4 5 65 0 Lower 43 5 52 survey 1 survey 2 survey 3 1959/60 1985/86 2015/16/17 UpperUpper Sabie Sabie River River- adjusted 1400 SABIE RIVER 1200 1000 Dipseudopsidae Ecnomidae 800 Ecnomidae Philopotamidae • Although Upper 600 Philopotamidae

Leptoceridae Abundance Sabie lost Abundance Leptoceridae 400 Hydroptilidae Hydroptilidae Dipseudopsidae, 200 Hydropsychidae Hydropsychidae diversity is still high 0 survey 1 survey 2 survey 3 • But abundance 1959/60 1985/86 2015/16/17 declines LowerLower Sabie Sabie River River- adjusted • Lower Sabie looks 1400 good in survey 3 1200

1000 Dipseudopsidae Ecnomidae 800 Ecnomidae Philopotamidae 600 Philopotamidae

Leptoceridae Abundance Sab S1 S2 S3 Abundance Leptoceridae 400 Hydroptilidae Upper 1 5 65 Hydroptilidae 200 Hydropsychidae Hydropsychidae Lower 54 5 65 0 survey 1 survey 2 survey 3 1959/60 1985/86 2015/16/17 SUMMARY

• Dipseudopsidae have been collected as adults rather than larvae – this family is easily missed during surveys (one has to actively look for them) • abundance and diversity seems to decline on the Crocodile River • Sabie River has been more diverse than the Crocodile River in the past also shown by the recent survey – this river still needs looking after though! • Recent survey could ring alarm bells with regards to decline in diversity OTHER RESULTS FROM THIS PROJECT

(1) New southern distribution records are being added for species known from Central Africa, (2) about 7 new species have been found in only one family of caddis flies (Leptoceridae) and only in one order! For one of these we need a name (see poster session tomorrow evening) NEXT STEPS

(1) Important invertebrate groups need to be analysed • other important indicator orders should be analysed: Ephemeroptera (mayflies), Odonata (dragon and damselflies), Plecoptera (stoneflies), etc. (2) Species level analysis for diversity decline and detecting loss of species over time (3) drivers of this decline need to be identified (4) action needs to be taken to protect aquatic diversity in KNP rivers (5) long-term monitoring is key • The situation needs to be monitored by follow-up surveys to enable comparison of snapshots in time in the future as well (6) establish DNA barcoding reference library • To enable quick species identification for species level diversity surveys and to confirm new species SKUKUZA BIOLOGICAL REFERENCE COLLECTION

Guin Zambatis Curator

Also housing aquatic invertebrate reference collection of survey 3!! Acknowledgements: Hendrik Sithole, Purvance Shikwambana, Lyndall Pereira da Conceicoa, Ina Ferreira, Sean Marr, Musa Mlambo & John Midgley for field assistance. Robin Petersen and the Scientific Services of the KNP for logistics assistance SanParks for accommodation Rensen Thete, Moffat Mambane and Isaac Sedibe, our guards. Kek Soxujwa, Nonkazimulo Mdidimba and Zezethu Mnqeta for help with sorting and cataloguing of samples. Funding: NSCF, NRF (SANBI FBIP & Incentive funding), Rhodes University, SAIAB, GBIF (EU).

Grant No’s 85286, 98130