Report on the Danish Oceanographical Expeditions 1908-1910 to the Mediterranean and adjacent seas- Engraulidae-Clupeidae

Study Extent

The dataset proceeds from the report by Fage (1920), merging data from Thor winter and summer expeditions to the Mediterranean and adjacent seas (1908-1910), with data from Thor expeditions to the N-W Atlantic (1905 and 1906). Some data from the Red Sea are also present, although this area was not the target of the expedition.

Sampling

Fish larvae of the families Engraulidae and Clupeidae were sampled mainly by trawling with Young fish trawl and Petersen trawl, depending on the expedition. Both methods are most suitable for pelagic fish larvae rather than coastal ones, as reported by Schmidt (1912).

Quality Control

The dataset was digitized manually from scanned documents. Original names regarding taxonomy and sampling location were kept as a reference. At the same time taxon names were cross-checked against the World Register of Marine Species (WoRMS); while the original sampling coordinates were plotted using Google Earth in order to double check that they are located in the sea. All data were checked for inconsistencies, both for the range of values, but also compared to other datasets from the same series, collected at the same station. Any problematic records were recorded in a remarks field in the data.

Method steps

1. Abundance data related to larvae of Engraulidae and Clupeidae, present in the report by Fage (1920) were digitized. To link these data with the environmental information recorded in correspondence of each sampling and published in Schmidt's report (1912), an unique ID was assigned to each sampling event whenever possible. Consequently each record can be linked to a set of geographical coordinates, a date, temperature and salinity data. We consistently kept the information from Schmidt as main reference, also in case of mismatch, typos or missing information in Fage's report. As abundance data were broken down into different size classes, we kept the information, i.e. for each sampling event there might be different records if different size classes were present.

Fish from families Clupeidae and Engraulidae (order Clupeiformes)

1. Sardina pilchardus
   common name: sardine rank: species
2. Clupea harengus
   rank: species
3. Engraulis encrassicolus
   rank: species
4. Sardinella aurita
   common name: sardine rank: species
5. Sprattus sprattus
   common name: sprat rank: species
6. Clupeiformes
   rank: order

Mediterranean and adjacent waters