Dear Tomaso,

to my personal point of view I would classify plastic glasses as A1 (bottles), because this is closer than A12 (other) . Plates, however, would go to A12.

For untrained researchers and/or non-native speakers also other more common items might go to the wrong category. (If I don't know what a strapping band is, then I will not identify it in the catch as such.)

Therefore I would recommend to (1) translate the IBTS litter protocol, if needed and (2) hand a foto guide to the people on the ship.

I have started with the foto guide here: https://www.thuenen.de/en/fi/fields-of-activity/marine-environment/marine-litter/marine-litter-gallery/

If there are more fotos around, please tell me.

Dear Ulrike,

Thank you for your answer. The photo guide is very useful indeed. It could be useful producing a printable photoguide since onboard it may be difficult consulting the internet.

We are running a seafloor litter monitoring in the Adriatic Sea since 2011 and the next survey will be the next month, and I am planning to take some photos of specific items in order to create an archive that will be useful for future marine litter identification.

Coming to plastic glasses and plates, from this year we decided to make a little change to the IBTS protocol adding the category "A14. Food containers/wrappers" taken from the DEFISHGEAR protocol (http://mio-ecsde.org/wp-content/uploads/2014/12/Seafloor-litter_monitoring-methodology_continental-selves_final.pdf). I think these items, that are really very common in the area, may fit this category.

What do you think about it? Are these items common also in the Baltic Sea?

Have a nice day.

Tomaso

Dear Tomaso,

you are absolutely right: the photo guide should be printed out and handed to the people on the ship. However, I have not enough category-fotos yet. Even if we take a foto of every single litter item since years.

Of cause you can add new categories or any information you need. I assume that you are interested in the amount of food containers/wrappers in your sampling campaign - so this is the only way. But if you decide later to enter your data in a "IBTS-database" it should fit somehow. A14 could be a sub-category of A12 or something like that. Thank you for the link to DEFISHGEAR. This is interesting for me. There are so few links between mediterranean and North Sea/Baltic Sea monitoring.

It is interesting that you ask for plastic plates and glasses. In our litter catches there was only once a plastic glass (if I remember it right) and I have never seen a plate. But many plastic sheets we find in the North-Sea/Baltic Sea are food-related. It seems that you are closer to the litter sources.

Thank you for recommending my publication.

Best wishes,

Ulrike

Dear Ulrike,

I guess the plastic plates and glasses come from vessels, mainly fishing vessels. Fishermen use throwaway cutlery and dishes and then some of them throw them away at sea (I saw it with my eyes), unfortunately.

I saw in the Thunen-Institut website that your institute is working on marine litter and plastic (project PlasM) in the Baltic Sea. Are you planning to open any position on this topic?

Best regards,

Tomaso