Here we provide three new Holocene (11–0 cal ka BP) alkenone-derived sea surface temperature (SST) records from the southernmost Chilean fjord region (50–53°S). SST estimates may be biased towards summer temperature in this region, as revealed by a large set of surface sediments. The Holocene records show consistently warmer than present-day SSTs except for the past ~ 0.6 cal ka BP. However, they do not exhibit an early Holocene temperature optimum as registered further north off Chile and in Antarctica. This may have resulted from a combination of factors including decreased inflow of warmer open marine waters due to lower sea-level stands, enhanced advection of colder and fresher inner fjord waters, and stronger westerly winds. During the mid-Holocene, pronounced short-term variations of up to 2.5°C and a cooling centered at ~ 5 cal ka BP, which coincides with the first Neoglacial glacier advance in the Southern Andes, are recorded. The latest Holocene is characterized by two pronounced cold events centered at ~ 0.6 and 0.25 cal ka BP, i.e., during the Little Ice Age. These cold events have lower amplitudes in the offshore records, suggesting an amplification of the SST signal in the inner fjords.

We present data on the occurrence of the invasive ctenophore Mnemiopsis leidyi in Norway after the initial observations made in 2005. Our data comes from several net sampling investigations conducted along the Norwegian coast in 2008–2014, as well as beach seine bycatch from the south coast (September–October 2005–2014). In 2008–2010, M. leidyi occurred in moderate abundances (≤0.56 lobate ind m−3) during autumn, with northernmost observations from Trondheimsfjord. Mnemiopsis leidyi was not observed in 2011–2012 and was scarce in 2013, but in 2014 it was again abundant along the south and west coasts. While temperature and salinity conditions along the Norwegian south coast and its fjords are sufficient for survival and reproduction by M. leidyi, temperature may limit egg production rates. Biological factors including food limitation as well as competition and predation by native gelatinous predators can also constrain populations. Mnemiopsis leidyi populations in Norway are likely to exhibit source–sink dynamics, with advective losses and suboptimal conditions preventing overwintering in large areas along the coast. The presence of M. leidyi in the southern North Sea, coupled with the cyclonic circulation pattern, suggests that outbreaks may nevertheless be expected in years with favourable conditions and/or significant inflow from the southern North Sea. Climate change could enhance reproduction of M. leidyi in Norway and protected inner fjords may offer a suitable habitat for establishment of local populations in the future.

During a 2005 scientific cruise in Storfjord in Møre, Norway, a previously undescribed co-occurrence between the wood boring bivalve Xylophaga dorsalis and the pogonophoran annelid (Sibglinidae) Sclerolinum brattstromi was discovered. The pogonophoran was lining burrows made by the bivalve, and surrounded it in a glomerulus-like structure. Based on observations, we hypothesize that the deep burrows of X. doralis produce an environment favourable to S. brattstromi. Interestingly, both bivalve and annelid are dependent upon symbiotic microorganisms, and thus raising the possibility that the relationship between these species is driven by their bacterial symbionts, or their utilization of the common redox boundary.