This dataset consists of the results of the genetic comparison of different species of the genus Jaera, a marine isopod, in the UK and USA. Jaera albifrons, J. forsmani, J. ischiosetosa, J. nordmanni and J. praehirsuta were collected from the underside of rocks at intertidal sites in the the UK. In the USA, J. posthirsuta, J. albifrons, J. ischiosetosa were similarly collected from sites in Maine and Massachusetts. Sample collection took place in 2015 and 2016. Sbf1 gene Restriction site Associated DNA (RAD) libraries were generated from total DNA using Illumina paired end DNA sequencing. In addition, individual microbiomes were characterised for Jaera albifrons, J. ischiosetosa, J. nordmanni, J. posthirsuta from UK populations using 16S rDNA metabarcode amplicon sequencing. The project aimed to assess parallel signatures of evolution across isolated populations and pinpoint regions of elevated genetic differentiation. All sampling and sequencing pipelines were undertaken by Marius Wenzel and Stuart Piertney (University of Aberdeen), with funding from NERC solo grant NE/M015661/1. Data are archived at the National Center for Biotechnology Information (NCBI).

This database contains information on the herbarium specimens held in the herbarium of the British Antarctic Survey (international code AAS) as well as information about specimens collected in the Antarctic and sub-Antarctic and held in other world herbaria. There are over 70 000 records, predominantly of mosses and lichens, but also of vascular plants, ferns, fungi and algae collected in Antarctic and sub-Antarctic regions as well as some from surrounding continents, particularly South America. The collection from South Georgia And The South Sandwich Islands started in 1775 and from Antarctica in 1834. Documents relating to the Herbarium are kept in the BAS Archives (LS2/4). The records can be searched and downloaded on: http://apex.nerc-bas.ac.uk/f?p=148:1. There is also a facility to see a distribution map of specimens retrieved by querying the database.

Three plant species, the leafy liverwort Cephaloziella varians and the angiosperms Deschampsia antarctica and Colobanthus quitensis, were sampled from 12 islands across a 1480 km latitudinal gradient from South Georgia through to Adelaide Island. Samples were collected to determine the abundance of dark septate fungi in Antarctic plant and soil communities and the effects of these organisms on plant growth. Where the target species were found in sufficient numbers to allow sampling, it proved possible to collect at least 10 samples of each species. At least 10 soil samples were collected from each site where Deschampsia was found. Plants, with intact roots and soil, were transported back to the UK using cool and frozen stowage. Additionally, intact live plants were transported to the UK in an illuminated cabinet. Seeds of the two key species (Deschampsia antarctica and Colobanthus quitensis) were also collected at Bird Island and South Georgia. As the exact months of the data collection were not provided, and the metadata standard requires a YYYY-MM-DD format, this dataset has been dated as 1st January for start date, and 31st December for stop date.

This study investigated the status of dark septate (DS) fungi in Antarctic plant and soil communities, with the aim of determining the abundance of DS fungi in plant roots and rhizoids, their taxonomic affinities and their symbiotic status. Abundances of fungal hyphae were recorded in roots and rhizoids, and fungi were isolated and identified. Sequencing of ITS (internal transcribed spacer) regions of rDNA indicated that some isolates share taxonomic affinities with fungi of known symbiotic status. Synthesis experiments assessed the effects of DS fungal isolates, including H. ericae, on the growth and nutrient balance of their host plants. Seeds of Deschampsia antarctica and Colobanthus quitensis were collected for use in ecophysiological experiments.

During field work in 2001 over 1600 specimens were collected from four main fossil plant assemblages: the 'Nordenksjold flora' from the Cross Valley Formation of Late Palaeocene age; and 3 floras from La Meseta Formation i) Flora2 from the Valle De Las Focas allomember, ~late Early Eocene, ii) Wiman Flora, Acantilados allomember, late Early/mid Eocene, iii) Cucullaea 1, Cuculleae 1 allomember Flora, early Late Eocene. In addition smaller collections of fossils from other parts of the La Meseta Formation were collected. The work concentrated on the Late Palaeocene and the Cuculleae 1 floras as these were the best preserved and had sufficient morphotypes for climate analysis. In the Late Palaeocene flora 36 angiosperm leaf morphotypes were identified, along with 2 pteridophytes (ferns), and podocarp and araucarian conifers. Discovery of several new leaf types indicates that the Tertiary floras from Antarctica were more diverse than previously thought.

Samples of early Tertiary age fossil wood and leaves were collected from Seymour Island, Antarctic Peninsula, in 2001. Fossils from Palaeogene strata were studied to determine the nature of vegetation response to the fundamental change from greenhouse to icehouse climates in Antarctica. Palaeoclimate data was derived using CLAMP (Climate Leaf Analysis Multivariate Program) and several Leaf Margin Analysis (LMA) techniques based on the physiognomic properties of the leaves. Climate interpretation of the fossils produced new data on terrestrial climate change at high latitudes and were used to test and validate climate models, and to establish whether climate-induced changes in biodiversity occurred in a gradual or punctuated manner.

Macaroni penguins spend the winter at sea and return to colonies on land during the austral spring to reproduce. Arrival weights of male and female Macaroni penguins on Bird Island, South Georgia have been monitored since 1988. The current protocol is that 50 males are weighed on 28th October and 50 females on 8th November. This work was funded by Natural Environment Research Council (UK) core funding to the British Antarctic Survey.

The breeding success (calculated from nest and chick counts) of Macaroni penguins is monitored annually at Bird Island, South Georgia. A transect is used to estimate the incubating nests and chicks hatched in the large colony at Goldcrest Point where counts have been made since 1976. The number of incubating nests and chicks reaching fledging stage in the whole of the smaller colony at Fairy Point are counted and data exist from 1982 onwards. This work was funded by Natural Environment Research Council (UK) core funding to the British Antarctic Survey.

100 nests in designated Adelie and Chinstrap penguin colonies are marked and then regularly monitored. Data are collected on when eggs are laid in each nest, when they hatch, when eggs or chicks are lost, and when chicks become unguarded. Data exist from 1996 onwards. For Adelie penguins, 100 nests in a colony designated A41 was monitored between 1996 and 2002, from 2003 onwards 100 nests in a colony designated A39 were monitored. For Chinstrap penguins, 100 nests in a colony designated A69 were monitored between 1996 and 2015, from 2016 onwards, 100 nests in a colony designated C66 were monitored. No data were collected in the 1997-98, 1999-2000 and 2010-2011 seasons. To calculate the annual hatching date a binomial model was fitted using the proportion of nests containing one or more chicks as the response variable and the date in days after 1 Oct as the explanatory variable. This model was fitted for each species and year separately. The dose.p function in the MASS package in R was used to derive the day when 50% of nests contained one or more chicks to produce the mean hatching date for each species-year combination. Mean laying dates were back-calculated from the mean hatching dates by subtracting the average incubation periods for each species (35 days for Adelies and 36.4 days for chinstraps, which are relatively constant between years). This has been calculated for data from 1996 to 2016.

The breeding success (calculated from nest and chick counts) of Gentoo penguins is monitored annually at Bird Island, South Georgia. The number of incubating nests and chicks reaching fledging stage are counted in several Gentoo penguin colonies. Data exist from 1982 onwards. This work was funded by Natural Environment Research Council (UK) core funding to the British Antarctic Survey.