1Dr. Mike Joy
Senior Lecturer; Environmental Science/Ecology
Ecology group-Institute of Agriculture and Environment -(PN-624)
Te Kura Matauranga o nga Taonga a Papatuanuku
Private Bag 11 222
Palmerston North 4442
Purpose and Summary
This report was commissioned by Gina Wilson to give both an indication of the ecological value of the stream (Fish Creek) that flows though her property and to assess the severity of damage to the stream caused by earthworks in and around the stream from an upstream land owner.
The authors of this report have had considerable experience in researching native fish ecology, their habitat requirements and assessment of freshwater environmental impacts (see appendix for a sample of related publications and reports).
On May 20th 2013 the authors carried out a daytime visual assessment of the stream bed both above and below the area where works had been carried out approximately 12 months earlier. That night a spotlight survey for fish fauna was conducted downstream of the works using New Zealand standard protocols (Joy et al. 2013a, b).
The visual inspection revealed obvious increased deposited sediment downstream of the earth works, and no sign of any above. The fish survey revealed a total of five fish and 2 decapod species. The decapods were the threatened endemic freshwater crayfish koura and the endemic shrimp, parataya. Four of the fish were native, the non-native was trout. Three of the four native fish are endemic and threatened species.
Fish Creek is a rare and fragile freshwater stream habitat containing threatened fish and decapod species and flows into an internationally renowned tourist attraction. There has been obvious damage to the freshwater ecosystem and there is no sign of any mitigation one year after the impact.
Fish Creek flows from the Kahurangi National Park into the Waikoropupu Springs catchment near Takaka. The stream is an increasingly rare example of a lowland stream that remains forested from its headwater down a significant length of its catchment. Moreover the fact that it is largely spring fed means that it provides a year round stable habitat for indigenous stream fauna. The ecological value of this stream is exceptionally high and it provides significant habitat for numerous threatened native fish species.
Impacts of Sediment and Vegetation Clearance on Native Fish
One of the most important aspects of native fish habitat is the availability of interstitial spaces between cobbles in the stream substrate. Recent research has shown these spaces to be particularly important for species such as redfin bullies and kokopu that can burrow down to depths of one meter or more and the majority of their lives are spent in these refugia (McEwan and Joy 2011, 2013). The research showed that these nocturnal endemic species spend the majority of the daylight time down in the substrate; consequently, sediment deposition on the stream bed destroys this crucial habitat. Overhanging vegetation is another important aspect as it provides shading which regulates temperature and algae growth, as well as terrestrial insects and leaf litter that are significant sources of food for fish and koura.
The earthworks upstream of Gina Wilson’s property took place in March/April 2012 and were significant especially given the relatively unmodified state of the stream. A track was carved down to the streams edge, where a platform was cleared (on both sides of the stream) destroying a wetland and stream riparian vegetation in the process. It is likely that a significant amount of sediment entered the stream at the time the works were completed and subsequently in high rainfall events. Consequently, the sediment impacts are still obvious a year later.
Approximately 100 m of stream was walked and studied below where earth works had taken place, roughly one year previous to this survey. In addition approximately 50 m of stream was walked above the earthworks site. There was clearly much more sediment present within the substrate downstream of the earthworks compared to upstream, see photos below.
A spot light survey for fish was carried out downstream of the earthworks site. This survey revealed a diversity of species that would be expected from a stream of high ecological value. Five species of fish, koura (freshwater crayfish) and Paratya (freshwater shrimp) were found. See table 1.
Discussion and Recommendations
The amount of sediment deposited can be assessed using the guidelines for sediment assessment3 and this assessment should have been done by the Tasman District Council immediately after the event and again later. It is clear that one year after the event, if this methodology were applied, quantifiable differences in deposition above and below the earthworks site would be clearly revealed. Because of the considerable length of time between when the works were conducted and the time that this survey was completed, it is likely that the majority of sediment has already moved through the area surveyed. However, because the area of stream immediately around where the works were conducted has not been re-vegetated it is highly likely that sediment will continue to enter the stream whenever there is a high rainfall event.
It is generally considered best practice to conduct fish surveys between the months of September and April due to warmer weather when fish are not buried into the substrate as they are in the cooler months. Because of this, it is likely that the numbers of fish found in the survey were underestimated and the fact that four native species were found in late May is an indication of the high ecological integrity of the stream itself. However, over time the supply of sediment from the un-remediated earthworks will fill much of the habitat utilised by these fish, reducing their numbers significantly.
It is therefore recommended that the earthworks site is remediated immediately by re-establishing riparian vegetation and undertaking sediment control around the carved track. In addition, sediment monitoring should be conducted using standard protocols2 now and after high rainfall to provide a comparison for monitoring after remediation work is completed. It is also recommended that future management of the stream needs to recognise the increasingly rare ecological integrity it possesses and to appropriately conserve it.
2 Allibone, R., B. David, R. Hitchmough, D. Jellyman, N. Ling, P. Ravenscroft, and J. Waters. 2010. Conservation status of New Zealand freshwater fish, 2009. New Zealand Journal of Marine and Freshwater Research 44:271-287.
Joy, M. K., B. O. David, and M. D. Lake. 2013a. New Zealand freshwater fish sampling protocols Pt.1: Wadeable river and streams. Field guide. The Ecology Group, Institute of Natural Resources.
Joy, M. K., B. O. David, and M. D. Lake. 2013b. New Zealand Freshwater Fish Sampling Protocols: Part 1- Wadeable Rivers and Streams. Massey University, Palmerston North.
McEwan, A. J. and M. K. Joy. 2011. Monitoring a New Zealand freshwater fish community using passive integrated transponder (PIT) technology; lessons learned and recommendations for future use. New Zealand Journal of Marine and Freshwater Research 45:121-133.
McEwan, A. J. and M. K. Joy. 2013. Habitat use of redfin bullies (Gobiomorphus huttoni) in a small upland stream in Manawatu, New Zealand. Environmental biology of fishes In Press.
1) Refereed papers and book chapters
Joy, M. K. and R. G. Death. 2013. Freshwater biodiversity.in J. Dymond, editor. Ecosystem Services in New Zealand : Conditions and Trends. (In press) Landcare, Palmerston North.
McEwan, A. J. and M. K. Joy. 2013. Habitat use of redfin bullies (Gobiomorphus huttoni) in a small upland stream in Manawatu, New Zealand. Environmental Biology of Fishes (1) 1 -12.
Joy, M. K. 2012. Water quality. A chapter in: Beyond Rio: New Zealand’s Environmental Record Since the Original Earth Summit. World Wildlife Fund Wellington.
Schwendel, A. C., Joy, M. K., Death, R. G., & Fuller, I. C. (2011). A macroinvertebrate index to assess stream-bed stability. Marine and Freshwater Research, 62(1), 30-37.
Schwendel, A. C., Death, R. G., Fuller, I. C., & Joy, M. K. (2011). Linking disturbance and stream invertebrate communities: how best to measure bed stability. Journal of the North American Benthological Society, 30(1), 11-24.
McEwan, A. J., & Joy, M. K. (2011). Monitoring a New Zealand freshwater fish community using passive integrated transponder (PIT) technology; lessons learned and recommendations for future use. New Zealand Journal of Marine and Freshwater Research, 45(1), 121-133.
Tonkin, J. D., R. G. Death, and M. K. Joy. 2009. Invertebrate drift patterns in a regulated river: dams, periphyton biomass or longitudinal patterns? River Research and Applications 25:1219-1231.
Rowe, D. K., S. Parkyn, J. Quinn, K. Collier, C. Hatton, M. K. Joy, J. Maxted, and S. Moore. 2009. A Rapid Method to Score Stream Reaches Based on the Overall Performance of Their Main Ecological Functions. Environmental Management 43:1287-1300.
McEwan, A. J. and M. K. Joy. 2009. Differences in the distributions of freshwater fish and decapod crustaceans in urban and forested streams in Auckland, New Zealand. New Zealand Journal of Marine and Freshwater Research 43:1115-1120.
Lewis, R. M., A. Bergeren, D. Armstrong, R. Boulton, and M. K. Joy. 2009. Artificial nest use to predict nest survival at reintroduction sites. New Zealand Journal of Ecology 33:40-51.
Atkinson, N. K., and M. K. Joy. 2009. Longitudinal size distributions of bluegill bullies (Gobiomorphus hubbsi) and torrentfish (Cheimarrichthys fosteri) in two large New Zealand rivers. New Zealand Journal of Marine and Freshwater Research 43: 643-649
Atkinson, N., and M. K. Joy. 2008. Response of Gobiomorphus hubbsi (bluegill bully) to odours of conspecific fish in the presence of natural stream odours: does habitat have an influence? New Zealand Journal of Marine and Freshwater Research 42: 173-180
Olden, J. D., M. K. Joy, and R. G. Death. 2006. Rediscovering the species in community-wide predictive modeling. Ecological Applications 16:1449-1460.
Low, M., M. K. Joy, and T. Makan. 2006. Using regression trees to predict patterns of male provisioning in the stitchbird (hihi). Animal Behaviour 71:1057-1068.
Joy, M.K. & Death, R.G. (2005). Neural network modelling of freshwater fish and macro-crustacean assemblages for biological assessment in New Zealand. In Modelling community structure in freshwater ecosystems (eds S. Lek, M. Scardi, P.F.M. Verdonschot, J.P. Descy & Y.S. Park), pp. 518. Springer, Berlin Heidelberg New York.
Joy, M.K. & Death, R.G. (2004) Predictive modelling and spatial mapping of freshwater fish and decapod assemblages: an integrated GIS and neural network approach. Freshwater Biology, 49, 1036-1052.
Joy, M.K. & Death, R.G. (2004) Application of the index of biotic integrity methodology to New Zealand freshwater fish communities. Environmental Management, 34, 415-428.
Olden, J.D., Joy, M.K., & Death, R.G. (2004) An accurate comparison of methods for quantifying variable importance in artificial neural networks using simulated data. Ecological Modelling, 178, 389-397.
Death, R.G. & Joy, M.K. (2004) Invertebrate community structure in streams of the Manawatu-Wanganui region, New Zealand: the roles of catchment versus reach scale influences. Freshwater Biology, 49, 982-997.
Joy, M. K., and R. G. Death. 2003. Biological assessment of rivers in the Manawatu-Wanganui region of New Zealand using a predictive macroinvertebrate model. New Zealand Journal of Marine and Freshwater Research 33:367-379.
Joy, M. K., and R. G. Death. 2003. Assessing biological integrity using freshwater fish and decapod habitat selection functions. Environmental Management 32:747-759.
Joy, M. K., and R. G. Death. 2002. A discriminant analysis investigation of reference site fish assemblages in the Manawatu-Wanganui region, North Island, New Zealand. Verhandlungen der Internationalen Vereinigung fur Theoretische und Angewandte Limnologie 28:319-322.
Joy, M. K., and R. G. Death. 2002. Predictive modelling of freshwater fish as a biomonitoring tool in New Zealand. Freshwater Biology 47:2261-2275.
Joy, M. K., and R. G. Death. 2001. Control of freshwater fish and crayfish community structure in Taranaki, New Zealand: dams, diadromy or habitat structure? Freshwater Biology 46:417-429.
Joy, M. K., and R. G. Death. 2000. Development and application of a predictive model of riverine fish community assemblages in the Taranaki region of the North Island, New Zealand. New Zealand Journal of Marine and Freshwater Research 34:243-254.
Joy, M. K., and R. G. Death. 2000. Stream invertebrate communities of Campbell Island. Hydrobiologia 439:115-124.
Joy, M. K., I. M. Henderson, and R. G. Death. 2000. Diadromy and longitudinal patterns of upstream penetration of freshwater fish in Taranaki, New Zealand. New Zealand Journal of Marine and Freshwater Research 34:531-543.
2) Selected Reports
Joy, M. K. 2013. Freshwater fish predictive modelling for bioassessment; A scoping study into fish bioassessment models in New Zealand; A report to the Ministry for the Environment. Wellington.
Joy, M. K. 2013. A fish index of biotic integrity for the Tasman Nelson District. Massey University.
Joy, M. K., B. O. David, and M. D. Lake. 2013. New Zealand freshwater fish sampling protocols Pt.1: Wadeable river and streams. Field guide. The Ecology Group, Institute of Natural Resources.
Joy, M. K., B. O. David, and M. D. Lake. 2013. New Zealand Freshwater Fish Sampling Protocols: Part 1- Wadeable Rivers and Streams. Massey University, Palmerston North.
Joy, M. K. and N. K. Atkinson. 2012. Salmonids and Native Fish in New Zealand; Are Trout to Blame for the Decline in Native Fish? , A report to Fish and Game New Zealand. Wellington.
Worner, S. P., Takayoshi, I., Leday, G., & Joy, M. K. (2010). Surveillance Tools for Freshwater Invertebrates; MAF Biosecurity Technical Paper: Bio-Protection Research Centre Lincoln University.
Joy, M. K. (2009). Temporal and land-cover trends in freshwater fish communities in New Zealand’s rivers: an analysis of data from the New Zealand Freshwater Database – 1970 – 2007 A report to the Ministry for the Ministry for the Environment: Massey University
James, A., and M. Joy. 2009. Prioritisation for restoration of out-flow stream habitat of coastal wetlands on the west coast of the Manawatu-Wanganui region. A report to Horizons Regional Council EnviroLink Contract
Belgrave, M., A. Bennett, J. Millner, A. James, M. Joy, D. Belgrave, S. Gardiner, J. Procter, and J. Watson. 2008. Raukawa Waterways and Environmental Impact. Massey University.
James, A., and M. K. Joy. (2008). A preliminary assessment of potential barriers to fish migration in the Manawatu River catchment, North Island, New Zealand. A report to Horizons Regional Council EnviroLink Contract Ref: 437-HZLC45, Massey University.
Joy, M. K. 2008. A Fish Index of Biotic Integrity using quantile regressions; A Fish QIBI for the Auckland Region. Massey University.
Joy, M. K. (2007). A new fish Index of Biotic Integrity using Quantile regressions: the Fish QIBI for the Waikato Region.
Kelly, F., T. Champ, T. McDonnell, M. Kelly-Quinn, S. Harrison, A. Arbuthnott, P. Giller, M. Joy, K. McCarthy, P. Cullen, P. Jordan, D. Griffiths, and R. Rosell. 2007. Investigation of the Relationship between Fish Stocks, Ecological Quality Ratings (Q-Values), Environmental Factors and Degree of Eutrophication. Environmental Protection Agency, Dublin.
Atkinson, N., and M. K. Joy. 2007. A Comparative Assessment of Three Prospective Dam Sites. Massey University, a report to Wellington Regional Council.
Atkinson, N., and M. K. Joy. 2006. Freshwater fish survey of the Whakatikei, Pakuratahi and Wainuiomata catchments. Massey University – Ecology.
Rowe, D., Quinn, J.F., Collier, K., Hatton, C., Joy, M.K., Maxted, J., Moore, S.J., & Parkyn, S.M. (2005). Ecological valuation: a method for scoring the ecological performance of perennial Auckland streams, Rep. No. HAM2004-073. national Institute of Water and Atmospheric Research, Hamilton.
Joy, M.K. (2005). A fish Index of Biotic Integrity (IBI) for the Wellington Region. Massey University, Palmerston North.
Joy, M.K. (2005). A Fish Index of Biotic Integrity (IBI) for the Waikato Region. Massey University, Palmerston North.
Joy, M.K. (2005). Point-click-fish a predictive model of fish occurrence for the Hawkes Bay region. Centre for Ecosystem Modelling and Management; Massey University, Palmerston North.
Joy, M.K. (2004). A Predictive Bioassessment Model using Fish for Southern Ireland. Massey University, Palmerston North.
Joy, M.K. (2004). A Fish Index of Biotic Integrity (IBI) for the Auckland Region. Massey University, Palmerston North
Joy, M. K. 2002. Freshwater fish survey of the Wellington Region a report to the Wellington Region Council. Massey University, Palmerston North.
Joy, M. K. 2002. Freshwater fish survey of the Wellington Region: a report to the Wellington Regional Council. A report to the Wellington regional Council Massey University, Palmerston North.
Joy, M. K. 2002. Lake Pounui Fish Survey. A report prepared for the Wellington Regional Council Massey University, Palmerston North.
Joy, M. K., and R. G. Death. 2002. The potential for enhancement of fish communities of a fish pass on the Orongorongo Intake Dam. A report to the Wellington Regional Council. Massey University, Palmerston North.
Phillips, J., and M. K. Joy. 2002. Native fish in the Manawatu-Wanganui Region. State of Environment Report 2002/EXT/489, horizons.mw, Palmerston North.
Rebergen, A. R., and M. K. Joy. 1999. Freshwater fish survey of the Aorangi Range, Wairarapa. Department of Conservation, Masterton.
Joy, M. K. 1999. Freshwater fish in the upper Manawatu River: a contribution to a life supporting capacity study. A Report to the Manawatu-Wanganui Regional Council Massey University, Palmerston North.
Joy, M. K. 1999. Freshwater fish survey of the Manawatu dune lakes. A Report to the Manawatu-Wanganui Regional Council Massey University, Palmerston North.
Joy, M. K. 1999. Native Fish Diversity and Distribution in Selected Tributaries of the Oroua River: a contribution to a Study of the Life Supporting Capacity of the Oroua River. A Report to the Manawatu-Wanganui Regional Council Massey University, Palmerston North.
Joy, M. K. 1998. Freshwater fish diversity and distribution in the Ohakune area: a contribution to a study of the environmental impact of vegetable washing. A report to the Manawatu-Wanganui Regional Council Massey University, Palmerston North.
Joy, M. K. 1998. Native fish diversity in the Oroua River and tributaries: a contribution to a study of the life supporting capacity of the Oroua River. A report to the Department of Conservation and the Manawatu-Wanganui Regional Council.