Literature:
- Bos, F. & M. Wasscher (1997) Veldgids nr 9: Veldgids Libellen. KNNV, Utrecht.
- Brochard, C., D. Groenendijk, E. van der Ploeg & T. Termaat (2012) Fotogids larvenhuidjes van libellen. KNNV Uitgeverij, Zeist.
- Brochard, C. & E. van der Ploeg (2014) Fotogids larven van libellen. KNNV uitgeverij, Zeist.
- Dijkstra, K.-D. (2008) Libellen van Europa: veldgids met alle libellen tussen Noordpool en Sahara. Tirion Uitgevers BV, Baarn.
- Wendler, A. & J.H. Nuss (2002) Libellen van Noordwest-Europa. Jeugdbonduitgeverij, Utrecht.
Imago observations:
- All individuals are caugth with a specific insect net.
- Detailed photographs are taken from all body parts.
- After documentation the adult dragonfly it is released.
- Photographs are stored in a database.
- Observations are uploaded to Laij.fi (formerly Hatikka.fi).
- See figure 2 for the distribution of observation days during the year.
Exuvia observations:
- Waterbodies are visited from land or from the water by rowing boat or canoe. If possible, I walk in the water along the coastline.
- Especially in case of peat bog vegetation, it often is difficult to move close enough to the water to collect exuvia.
- Every metre of coastline is investigated for exuvia. However, only for the small ponds the entire coastline is investigated. Larger ponds are covered partially.
- Also, now and then, the vegetation between 0 – about 5 m distance to the open water is investigated.
- Exuvia are identified to species under a 40x stereo microscope using Brochard et al. (2012).
- Aeshnidae are classified to male or female.
- Exuvia are stored in pots per location and year (dates within a year are mixed).
- A selection of exuvia is used in a reference collection.
- Observations are uploaded to Laij.fi (formerly Hatikka.fi).
- See figure 2 for the distribution of observation days during the year.
Libellen_Liesjarvi_excursiedagen
Figure 2. Distribution of excursion days since 2004 (adults) and 2016 (exuvia).
Figure 2. Distribution of excursion days since 2004 (adults) and 2016 (exuvia).