Monitoring Protocol for Floating and Ingested Marine Litter

Currently available data on marine litter in the Mediterranean and in Europe are often insufficient and not comparable across marine regions and surveys. More consistent, coherent, and comparable marine litter data are needed in order to increase our knowledge, implement concrete actions for marine protection, and monitor their effectiveness. To address this issue, two protocols have been developed in the context of the Interreg MED MedSeaLitter project to provide a standard way to collect data on floating marine litter and on marine litter ingestion by sea turtles (Caretta caretta), fishes (recommended species: bogue, Boops boops), and polychaeta.

Technological infrastructure

The technical requirements to apply the protocol are higher in the case of the use of aircrafts and drones, and for the ingestion of micro-litter in biota, while they are lower for the visual observations from ferries and small-medium boats, and for the ingestion of macro-litter in sea turtles. A detailed description of the technological infrastructure required for each tool is included in the published protocol.

Training

The training and expertise required depend on the technique used (see the published protocol for detailed specifications). Specialised training and expertise are necessary to use aircrafts and drones, and to apply the methods related to the extraction of ingested litter, while the use of ferries or small-medium boats for visual observations has lower training requirements. Specific training for pilot MPAs has been organised in the context of MedSeaLitter in spring and summer 2019.

Investment

Approximate estimations of the cost of each technique in the protocols have been performed; they are included in the published protocol. These range from the lower cost Pilot areas: Capo Carbonara MPA, Italy; Barcelona–Civitavecchia transect; Livorno-Bastia transect; Palermo-Cagliari transect; Palermo-Tunis transect; Ancona-Igoumenitsa-Patras transect Monitoring Protocol for Floating and Ingested Marine Litter Monitoring tool Capo Carbonara MPA Cagliari Livorno Civitavecchia Patras Bastia Palermo Tunis Barcelona MEDSEALITTER Ancona-Igoumenitsa This tool is part of a Mediterranean Toolkit for Biodiversity Protection developed by the PANACeA partnership: of visual observations by ferries (in the 1,000-50,000 Euro range) to the higher cost of using aircrafts and monitoring micro-litter ingestion by invertebrates (higher than 50,000 Euro). The exact cost will depend on staff costs, existing equipment, and whether or not the protocol makes use of existing monitoring programmes and/or maritime operations.

Concept

The protocol proposes slight modifications to the basic data collection sheet adopted at the European level. Recommendations are also made on using ferries and sailing boats, and on using automatic photography from UAVs and manned aircrafts. In relation to the ingestion of marine litter, the protocol focuses on the loggerhead sea turtle (Caretta caretta), fishes (recommended species: bogue, Boops boops), and polychaeta. In relation to the loggerhead sea turtle, the protocol addresses only the necropsy in dead animals, slightly modifying the existing European protocol, considering basic and optional parameters proposed to stakeholders according to their logistics and time constraints, and in coordination with another EU-funded project, INDICIT.

Recommended implementation frequency

Seasonality can play a key role in driving the variability in the amount and distribution of litter, which is linked to seasonal variation in oceanographic and anthropogenic factors. Thus, stratification of surveys for the different seasons is required. For floating marine litter, a minimum sampling frequency of one per year is required, although seasonal replication is recommended. A frequency of at least 5 surveys per season can be considered adequate to perform seasonal analyses within one year of monitoring.

Visual observations and automatic recording through photo/ video may be affected by weather/sea conditions. Costs may be high if using dedicated research vessels. Moreover, from large vessels and aircraft it is possible to detect only marine litter that is larger than 20 cm. Finally, the dimension of the objects at sea may be difficult to assess; to overcome this issue, the protocol suggests using a ruler with a string of fixed length, and measuring the apparent length of the object and the degree of distance from the horizon line, in order to have an estimation of the object’s real size. The monitoring of ingestion may depend on the geographic coverage of the species and the availability of animals.

Quantitative results

The application of the protocol allows for the collection of consistent, coherent, and comparable data on floating marine litter on both a large scale (i.e., at the Mediterranean basin level) and local scale (i.e., at an MPA level), and on ingested litter by biota.

Transfer potential

The protocol has been specifically developed for the Mediterranean, but it may be used to collect marine litter data in other marine contexts as well.

• The protocol developed by MedSeaLitter has been included in the review of the EU Guidance on Monitoring of Marine Litter in European Seas, in 2019.