Type and figured material from 'The Pliocene Bryozoa of the Countries' (Lagaaij, 1952) in the collection of the Royal Belgian Institute of Natural Sciences

Type and figured material of 32 species from Wilmarsdonk and Deurne-Zuid (Antwerp) featured in R. Lagaaij’s 1952 monograph ‘The Pliocene Bryozoa of the Low Countries’ is re-illustrated by scanning electron microscope, and catalogue details are given. The nomenclature of a number of species is updated. The Wilmarsdonk material, designated Scaldisian by Lagaaij, is considered to be from the Luchtbal Sands Member of the Lillo Formation

Alien species of <i>Bugula</i> (Bryozoa) along the Atlantic coasts of Europe

Three apparently non-native species of Bugula occur in marinas and harbours in Atlantic Europe. The most common, B. neritina, was known from a few sites in southern Britain and northern France during the 20th century, following its discovery at Plymouth by 1911. During the 1950-60s it was abundant in a dock heated by power station effluent at Swansea, south Wales, where it flourished until the late 1960s, while water temperatures were 7-10°C above ambient. It disappeared after power generation ceased, when summer temperatures probably became insufficient to support breeding. Details of disappearances have not been recorded but B. neritina was not seen in Britain between c1970 and 1999. Since 2000, it has been recorded along the south coast of England, and subsequently in marinas in the southern North Sea, Ireland and southern Scotland, well to the north of its former range, as well as along the Atlantic coast from Spain to The Netherlands. It has also been introduced to outlying localities such as the Azores and Tristan da Cunha. We report that this rapidly spreading form has the same COI haplotype as B. neritina currently invasive elsewhere in the world. B. simplex has been reported less, with 1950s records from settlement panels in some Welsh docks. It has not been targeted in most recent marina surveys but has been observed in southwest England, Belgium and The Netherlands. There are almost no recent records of B. stolonifera, though it was probably introduced to a few British and Irish ports prior to the 1950s. Its current status in most of western Europe is unknown but it has been reported as expanding throughout most of the world during the last 60 years. Having poorly known distributions, B. simplex and B. stolonifera should be recorded during future monitoring of alien species in Atlantic Europe. Illustrations to aid identification are included for all three species

Visualisation of the copepod female reproductive system using confocal laser scanning microscopy and two-photon microscopy

We examined mating behaviour in the harpacticoid copepod Tube battagliai Volkmann-Rocco, 1972, in particular the process of delivering spermatophore seminal contents to the female urosome. Labelling using 4′6′ diamidino-2-phenylindole (DAPI) coupled with two-photon confocal laser scanning microscopy successfully visualised the spermatophore and female internal reproductive system. Sections of the female urosome were imaged to examine seminal fluid stores. The female tissues were found to auto-fluoresce as red emission under green excitation, requiring no additional tissue labelling. DAPI-labelled seminal fluid stores were identified within the female reproductive system. The details observed agreed with previous descriptions of copepod reproductive anatomy and of spermatophores. Specimens cultured under pH 8.10 and a simulated ocean acidification scenario (pH 7.67) were compared for changes in reproductive anatomy and spermatophore size and site attachment. No differences were observed in spermatophore attachment or the female reproductive system but spermatophore size was reduced significantly at pH 7.67 compared with pH 8.10. This size reduction was, however, in proportion to an overall reduction in female body size at reduced pH. Confocal microscopy is shown here to be a valuable tool to investigate detailed reproductive processes in copepods

Genetic structure of populations of two species of Chthamalus (Crustacea: Cirripedia) in the north-east Atlantic and Mediterranean

Protein electrophoresis on starch gels was used to investigate population genetic structure of the barnacles Chthamalus montagui Southward and C. stellatus (Poli) over their north-east Atlantic and Mediterranean ranges. In each species, a single locus exhibited marked differentiation of allele frequencies between Atlantic and Mediterranean localities; in C. stellatus, genetic differentiation between the two basins had not previously been noted. In both species, mean heterozygosity per locus appeared higher in the Mediterranean samples than in the Atlantic, and Mediterranean populations had more alleles at the loci studied. Possible explanations for the differentiation between the Atlantic and the Mediterranean populations are discussed

Factors affecting fertilization success in two species of patellid limpet (Mollusca: Gastropoda) and development of fertilization kinetics models

Laboratory experiments were undertaken to examine fertilization success in the intertidal prosobranch limpets Patella ulyssiponensis and Patella vulgata. Alkalization of eggs (10 min in pH 9.0 sea water) prior to fertilization trials improved fertilization rates greatly. Fertilization success was found to be a function of sperm concentration, gamete age and contact time. Sperm concentration needed for optimum fertilization success in vivo ranged between 105 and 107 sperm ml–1 for both species although at higher concentrations the number of normally developing trochophore larvae decreased. For P. vulgata, sperm longevity (at a concentration of 106 sperm ml–1) did not exceed 6 h, whereas eggs of both species were fertilizable for up to 12 h. Maximum fertilization success occurred after 15–30 min gamete contact time. The Vogel et al. (Math Biosci 58:189–216, 1982) fertilization kinetics model is developed to allow for non-complete fertilizations under optimal sperm concentrations, and a new parameter fitting technique is developed to improve estimates of fertilization success for short gamete contact times

Developing an indicator of the abundance, extent and impact of invasive non-native species. Final report

This report describes an indicator of the abundance, extent and impact of invasive non-native species in Great Britain. The main ideas and options for the abundance indicator and for the impact indicator are considered. A third type of indicator, the annual rate of establishment of new non-native species, is outlined, with provisional data presented only for England. Most of the options for the abundance indicator do not in fact measure abundance, but use either frequency in samples or frequency in recording scheme data as a substitute. An exception is the Breeding Bird Survey, for which numbers of individuals are counted. Several well-recorded groups of organisms have no non-native species (e.g. butterflies and lichens) or exceedingly few non-native species (macro-moths). Datasets selected for the abundance indicator were the Breeding Bird Survey (birds and mammals), Countryside Survey (vascular plants), British Bryological Society data (bryophytes) and Marine Biological Society data (marine organisms). From samples of records in each species group, the non-native component was calculated as proportion of all species sampled. This provided a temporal trend in non-native proportions, which were calculated separately for England, Scotland and Wales. The GB trend was derived by combining the trends for each component country, weighted by the area of each. Finally, the overall trend was calculated as a weighted geometric mean of trends for each species group, converted to an index by dividing by a constant to start at 1 in the baseline year 1990. The weights applied were birds 20%, mammals 20%, vascular plants 30%, bryophytes 10% and marine organisms 20%. There were no suitable datasets from the freshwater environment. No direct measure of impact could feasibly be calculated for all invasive species in Great Britain. As a substitute, an indicator based on the extent of occupation by invasive species was adopted. The methodology for the indicator was based on a scheme developed by the Belgian Forum on Invasive Species. First, a list of the most invasive species was compiled, using a simplified environmental impact assessment protocol to assign species to threat categories. Then the extent of each invasive species was scored for 1960, 1970, 1980, 1990, 2000 and 2007, on a 5-point scale ranging from 0 (absent) to 4 (present in more than half the territory). Extent scores were added to obtain the indicator. Over the period 1990-2007, the mean indexed proportion of records of non-native species in samples of birds, mammals, plants and marine life rose by 23%. Except for mammals, the absolute proportion was still only about 1% of the total. The assessment protocol assigned 49 species in Great Britain to the highest threat category. There were 3 marine plants, 16 marine animals, 4 freshwater plants, 8 freshwater animals, 8 terrestrial plants and 10 terrestrial animals. Over the period 1990-2007, the summed extent scores of these invasive non-native species rose by 40%. The increase of invasive species was particularly large in the freshwater and marine environments. Although non-native species are a potential threat, they are still only a small proportion of the animals and plants to be found in most of the land area and coasts of Great Britain. Vertebrates stand out as the most invasive group. For all groups of organisms reported here, England was the country most affected by non-native species. Scotland was the least affected. Wales was intermediate. In 2008, values of the impact indicator for the three countries were respectively 135, 73 and 95. Most species groups showed a trend over time towards an increasingly non-native biota. If the indicator is to be developed further, the main priority is to include freshwater species in the abundance component. Because the list of invasive species depends on expert judgement, it needs to be reviewed and if necessary updated at regular intervals. Further analytical work is desirable, to improve the signal obtained from recording scheme data