Ciliate communities on macrofauna: There is a world to discover.

First description of epizoic ciliates on Bathyporeia including undescribed species.

Hardly visible with the naked eye, flourishing communities of epibiont species are often present on macrofauna. Examining Bathyporeia (small crustaceans of few millimeters in size, abundantly present in marine and estuarine waters) from Dutch waters showed that peritrich ciliates were present on 44% of the over 3500 specimens investigated. Although known for a range of other species including crustaceans, peritrich ciliates on Bathyporeia, when present also often abundantly present, were not described in detail before. Only d’Udekem d’Acoz (2004) mentions the common presence of ramified colonies of peritrich ciliates on appendages of Bathyporeia in his paper on the genus.

We discovered several types including solitary and colony-forming specimens, of which the most common species appeared to be Zoothamnium nanum (an epibiont species known from other small crustaceans like Gamarus species). However, also a likely sofar undescribed species of the genus Epistylis appeared to be common, and another type of Zoothamnium (that might be an undescribed species) was observed.

Findings on infestation patterns for different Bathyporeia species for different waterbodies and years and possible implications for basibionts (hosts) and epibionts are presented and discussed in a paper published in Crustaceana: Wijnhoven et al. (2018). Taking into account the common presence and large abundances on a variety of macrofauna species, indicates that epizoic ciliates might play a more important role in ecosystem functioning than is now recognized and/or understood. There is still a whole world to discover!

Photographs of peritrich ciliates on Bathyporeia sp.; a) Typical colonies of peritrich ciliates (most likely Zoothamnium nanum) attached to a peduncle of an antenna from Bathyporeia pilosa (specimen stained with Rose Bengal and preserved in formaldehyde) (1000x magnification); b) Typical colonies of peritrich ciliates (most likely Zoothamnium nanum) in detail (on a specimen stained with Rose Bengal and preserved in formaldehyde) (4000x magnification); c) Individual and small colonies of alive Zoothamnium sp. on peduncles from antenna 2 of an alive specimen of Bathyporeia sarsi (1000x magnification); d) A singular alive specimen of Zoothamnium nanum on Bathyporeia sarsi (4000x magnification) with its cilia out; e) Singular alive peritrich ciliates on Bathyporeia pilosa (4000x magnification) showing a specimen without a spasmoneme (Epistylis sp.); f) Singular and couples of peritrich ciliates on Bathyporeia pilosa (4000x magnification) where the lower specimen belonging to the genus Zoothamnium lacks transverse folds (Zoothamnium sp.).

Wijnhoven, S., Zwiep, K.L., Hummel, H. (2018). First description of epizoic ciliates (Sessilida Stein, 1933) on Bathyporeia Lindström, 1855 (Peracarida, Amphipoda) and infestation patterns in brackish and marine waters. Crustaceana 91(2),133-152.

Other study cited:

d’Udekem d’Acoz, C. (2004). The genus Bathyporeia Lindström, 1855, in western Europe (Crustacea: Amphipoda: Pontoporeiidae). Zool. Verh. Leiden 348, 3-162.

Overview alien species monitoring in the Western Scheldt

An overview on monitoring activities providing information on the presence of alien species among macrofauna, macro-algae and plankton in the Western Scheldt has  been prepared by Ecoauthor, GiMaRIS and eCOAST. Almost a hundred alien species were observed during the last 25 years, for which vectors of introduction are indicated. The study gives a nice overview of the efficiency of techniques to detect certain alien species groups and the habitats where new alien species are most likely be encoutered. In the meanwhile new alien species have been detected in the Western Scheldt and will amongst others be presented in the Ecoauthor Transect Monitoring report for 2017 coming available soon.

– Wijnhoven, S., Gittenberger, A., Faasse, M., Schellekens,T. (2017). Overview alien species monitoring in the Western Scheldt: Current status of monitoring efforts and presence of alien species among macrofauna and algae. Ecoauthor Report Series 2017 – 01, Heinkenszand, the Netherlands.

– Wijnhoven, S. (2016). Non-indigenous species presence and distribution in intertidal hard substrate environments of the Western Scheldt: Results of Transect Monitoring inventory of 2016. Ecoauthor Report Series 2016 – 01, Heinkenszand, the Netherlands.

Both, the Overview report as the Transect monitoring in the Western Scheldt are commissioned by the Office for Risk assessment and Research (BuRO) of the
Netherlands Food and Consumer Product Safety Authority (NVWA).

Living Planet Report – Salty and brackish nature in the Netherlands

Foto: ©Bert Ooms/WWF

WWF – The Netherlands (WNF) has published a nice report showing the recent trends in species richness in amongst others the Dutch North Sea, Wadden Sea and Delta waters. Ecoauthor also made a modest contribution to the interpretation of findings here.

The entire report:‘Wereld Natuur Fonds. 2017. Living Planet Report. Zoute en zilte natuur in Nederland. WNF, Zeist.’ (written in Dutch) can be found here.

Additional information can be found on the website of WNF (

Benthic Indicator Species Index to evaluate quality status North Sea

To evaluate habitat quality, sea floor integrity and ecological functioning of the Dutch North Sea the Benthic Indicator Species Index (BISI) has been dev eloped. The BISI is specifically developed to deliver to the Marine Strategy Framework Directive (MSFD) reporting, evaluate the effectivity of management measures and provide information for Habitat Directive-habitat evaluations. The BISI compares temporal patterns (absence/presence, or densities) of combinations of specific indicator species with predefined reference levels of these species that represent a good status. BISI can be used at different spatial scales (e.g. Exclusive Economic Zone (EEZ), Natura 2000 areas, specific ecotopes and habitats) and additionally provides evidence for possible causes and effects of observed patterns in quality status (developments).

The BISI is developed by Ecoauthor in cooperation with Wageningen Marine Research (WMR) commissioned by the Dutch Ministries of Economic Affairs (EZ) and of Infrastructure and Environment (IenM)).

The BISI is potentially applicable in other regions than the Dutch North Sea as well. At present Ecoauthor is amongst others working on the T2015 evaluation of the Dutch North Sea on basis of BISI and the adjustment of BISI for wider application.

The indicator is presented in:

Wijnhoven, S. & Bos, O.G. (2017). Benthische Indicator Soorten Index (BISI): Ontwikkelingsproces en beschrijving van de Nationale Benthos Indicator Noordzee inclusief protocol voor toepassing. Ecoauthor Report Series 2017-02, Heinkenszand, the Netherlands (written in Dutch).

With a protocol of application (written in English):

Wijnhoven, S. (2017). Protocol Benthic Indicator Species Index (BISI). Annex 1 of Wijnhoven & Bos (2017).

Myosotella denticulata not that rare in the Western Scheldt

At the moment Ecoauthor is monitoring the presence of non-indigenous species in the intertidal zone along the Western Scheldt (‘Westerschelde’). Besides valuable information on the distribution of exotic species (results will follow later this year), the monitoring also gives insights in populations of indigenous species. For the second year in row Myosotella denticulata (‘Meertandig muizenoortje’ in Dutch) is found to be common in the high intertidal parts near Bath. Myosotella denticulata is specifically found in the spaces between the blocks that pave the dikes. The ecological atlas (De Bruyne et al., 2013) records the species for just one 10×10 km gridcell in the entire South-western Dutch delta, although it is already mentioned that the species might be more common than suggested. We did also observe the species near Breskens and Hansweert in a similar habitat before (Wijnhoven et al., 2015).

Research is part of the Transect Monitoring project commissioned by the Netherlands Food and Consumer Product Safety Authority (NVWA).

  • De Bruyne, R., van Leeuwen, S., Gmelig Meyling, A., Daan, R. (2013). Schelpdieren van het Nederlandse Noordzeegebied. Ecologische atlas van de mariene weekdieren (Mollusca). Uitgeverij Tirion, Utrecht en Stichting ANEMOON, Lisse, 414 p.

  • Wijnhoven, S., Engelberts, A., Dekker, A. et al. (2015). Non-indigenous species inventory of estuarine intertidal areas; a comparison of estuaries and habitats using a hard substrte transect methodology. Pilot study wthin the frame of the INTERREG IV A 2 Seas project SEFINS commissioned by the NVWA. Monitor Taskforce Publication Series 2015-07, NIOZ-Yerseke, the Netherlands.


Celebrated the one-year anniversary of Ecoauthor


Celebrating the one-year anniversary of Ecoauthor

Celebrated the one-year anniversary of Ecoauthor with my dearest ones.

I would like to thank all clients and colleagues working with Ecoauthor, for the nice cooperation and making it a succesful first year. I am looking forward to continue the collaborations and to the new projects to come.

Best wishes, Sander Wijnhoven (owner of Ecoauthor)




Ecoauthor participated in trinational workshop Doggerbank

Last February the 8th, a trinational workshop on joint monitoring, evaluation and knowledge exchange concerning the Doggerbank was held in Hamburg. With several participants from Germany and the UK, Ecoauthor represented the Dutch government. Although monitoring programmes in the three countries are quite different, it is clear that cooperation will have benefits for each of the countries. As a first step, benthic monitoring data will be exchanged, and the various indicators in use will be applied on each others datasets. The tuning of evaluations should lead to a joint evaluation of the international Doggerbank region in the near future. Also joint monitoring activities are foreseen. doggerbank-monitoring-nl-v060217


Attention for Ecoauthor work in Newsletter ‘Informatiehuis Marien’

Since several months we are developing a Benthos-based Indicator system for the evaluation of the Dutch North Sea for the Dutch Ministry of Economic Affairs (EZ) and the Dutch Ministry of Infrastructure and Environment (I&M). The evaluation tool will specifically be used to report on the quality developments towards the Marine Strategy Framework Directive (MSFD) and evaluation of management regulations (i.e. fisheries restrictions) in Natura 2000 areas and other areas of special interest. The latest newsletter of the Marine Information and Data Centre (Informatiehuis Marien) has some attention for our work: ‘Measuring with benthic macrofauna‘. (The article is in Dutch).ihm-article



Ecoauthor has signed Framework Agreement with Rijkswaterstaat

Western Scheldt 2016Ecoauthor is happy that the Framework Agreement Biology concerning Specialist Advice and Methodology Development was awarded to us by Rijkswaterstaat (RWS-CIV, Dutch Ministry of Infrastructure and the Environment) for a range of competences in the field of Hydrobiology, Ecological Monitoring of Flora & Fauna, and Ecological Mapping. The Agreement is signed for three years. We are looking forward to a fruitful cooperation and are ready to put it in practice.




Developing the Benthos Indicator for the Dutch North Sea

At present Ecoauthor is working on the development of the National Benthos Indicator for evaluation of the Dutch North Sea for the Marine Strategy Framework Directive (MSFD) in cooperation with Wageningen Marine Research. designing-a-national-benthos-indicatorThe challenge is to develop a transparant indicator that will be used for various evaluations and reportings (e.g. MSFD, Habitat Directive, evaluation of Nature 2000 management and evaluation of effectivity of taken measures) that can act on the various spatial and temporal scales involved and will be indicative for causes of potentially observed changes as well. Yesterday we had some good discussions and valuable information exchange during an expert workshop as organized by the Ministry of Economic Affairs (EZ) and the Ministry of Infrastucture and the Environment (I&M) for which I like to thank all participants and the organizers.