Balanus improvisus (Darwin, 1854)


COMPILED BY: Anastasija Zaiko
CITATION OF THIS ENTRY: Zaiko A. 2005. Balanus improvisus. In: Baltic Sea Alien Species Database. S. Olenin, E. Leppakoski and D. Daunys (eds.).
INTERNET: http://www.corpi.ku.lt/nemo/mainnemo.html


TAXONOMY

Subtypus Invertebrata
Phylum Arthropoda
Class Crustacea
Subclass Cirripedia
Superorder Thoracica
Order Sessilia
Suborder Balanomorpha
Family Balanidae
Genus Balanus
Species Balanus improvisus (Darwin, 1854)
Common names Bay barnacle, Acorn barnacle

Balanus improvisus (Photo by Sergej Olenin)

IDENTIFICATION

The Bay barnacle has a low, cone-shaped calcareous shell made up of white to greyish plates (Weidema 2000). Wall typically conical, very smooth; walls never foldedlongitudinally. The opening is narrow and diamond shaped. Radii very narrow with rounded edges. Base radially calcareous (base of B. crenatus lacks this star-like ornamentation; base of B. balanoides is membranous), flat and thin, permeated by pores that do not generally run to the very centre of the basal plate (Leppäkoski 1999). The shells can remain in place long after the animal that constructed and inhabited it is dead. Like all sessile barnacles the Bay barnacle is hermafroditic (i.e. all individuals posses both male and female reproductive organs). it is also a facultative self-fertiliser, which may be a favourable trait when establishing and maintaining new populations (Weidema 2000).

INTRODUCTION AND DISTRIBUTION

Year ­ 1844
Area - Baltic Proper
Reference - Jansson 1994; Gruszka, 1999

in the entire Baltic Sea ­ Yes
in the area of primary introduction ­ Yes

North America, eastern coast

B. improvisus was first recorded in the Baltic Sea in 1944 at Königsberg (presently Kaliningrad). From this hypothetical dispersal centre it spread very rapidly and became common, especially in ports. It is thought to have invaded most of its present area of occurrence in the 1870s or, at latest, before the turn of the century. There were few records from the Swedish east coast before the 1920s (Leppäkoski 1999). By the 1990s the Bay barnacle reached its northernmost limit of distribution at the Northern Quark, at 630N. The easternmost point is at about 250E in the Gulf of Finland (somewhat east of Helsinki) (Weidema 2000).

Salinity range. The Bay barnacle is the most freshwater tolerant of the barnacles. Of all the estuarine barnacles B.improvisus can be found further inland where it avoids competition with native species. It is extremely euryhaline and eurythermal species which is absent only from Arctic and Antarctic seas. It is even present in the Red Sea, where salinity is 40 per mile. Activity optimum at 6-30 PSU. Maximal larval settlement is found in mid-salinities; does not reproduce in fresh water. (Jarvekiulg 1979; Leppäkoski 1999; Weidema 2000).
Temperature. The temperature range for B. imprvisus in the Baltic is 1.8 – 22.7 0C (Jarvekiulg 1979). Optimum conditions for free swimming nauplius larvae is around 14 0C (Leppäkoski 1999).
Tolerance to pollution. B. improvisus has a wide tolerance for oxygen concentration in the water; it can be met in the polluted parts of the Baltic, Black, Caspian and other Seas. Can stand 0.3 – 0.4 mg/l concentration of NH4 (Jarvekiulg 1979). Tolerant to eutrophication; preference for organically enriched sites in ports with good foraging conditions (filter feeder on detritus and phytoplankton) (Leppäkoski 1999). However, assessment of cytogenetic damage in Balanus improvisus (aneugenic effects) inhabiting the Baltic Sea at Butinge oil terminal has shown the high genotoxicity level in the zone of sewage effluents from Palanga town and Mazeikiai oil refinery plant. Extensive cytogenetic injuries in gonadal cells indicated the potential long-term hazards of pollutants to ecological health and integrity of these aquatic species (Barien 2002).
Preferable substrate. Inhabits sub-littoral, stony and rocky bottoms, often can be found on the ship hulls, hydro technical constructions, on the sluices, sometimes attaches to the crayfishes, crabs and other animals. It also can be met attached to algae (such as bladder wracj, Fucus vesiculosus) (Birshtain et al. 1968; Hayward, Ryland 1995; Weidema 2000). In the southern Baltic Balanus improvisus Darwin, the only representative of the Cirripedia, grow almost exclusively on the mussel Mytilus trossulus Gould, which is the dominant element of the bottom fauna in this area. The sporadic occurrence of this barnacle on another Baltic bivalve species, the cockle Cerastoderma glaucum Poiret, has also been noted. In September 1999 the author discovered B. improvisus on shells of the soft-shell clam Mya arenaria L. on the beach near Brzeźno (Gulf of Gdańsk). The presence of B. improvisus on M. arenaria could be further evidence of the tendency of barnacles to colonise all available habitats, even if they are not always optimal (Olszewska 2000).
Vulnarable (invasible) habitats. Brackish water bays and estuaries to shallow marine habitats (max. 6 m depth) with hard substrata (stones, rocky shores and man-made constructions such as breakwaters and ships). Its wide distribution indicate its potential of becoming established from warm temperate to tropical regions (Leppäkoski 1999). According to the data from literature Balanus can inhabit 0.5 – 90 m of water depth, to the author it was met in the 0.1 – 47 m of depth (the optimum is 0 – 19 m). It inhabits pseudolittoral and sublittoral.The minimum oxygen concentration can rich < 1 ml/l3. Prefers the stony and stony-sandy bottoms (Jarvekiulg 1979).
Reproduction. Although hermaphroditism is universal in sessile barnacles, only a few species are known to be facultative self-fertilisers. Some studies tested the ability of Balanus improvisus Darwin to self-fertilise. Individuals were observed to carry well-developed ovaries and well-developed testes at the same time. Fertilisation took place and the eggs developed to larvae in both isolated and communal individuals. Self-fertilisation appears to take place somewhat later than cross-fertilisation. These laboratory results on self-fertilisation in B. improvisus are supported by field observations, in which isolated individuals were found with fertilised egg masses. B. improvisus can thus be added to the list of facultatively self-fertilising cirripedes. The ability to self-fertilise is especially advantageous for individuals of a species such as B. improvisus, which often has sparse and isolated populations (Furman, Yule 1990).
 

THE ROLE IN THE BALTIC SEA ECOSYSTEM

Competition for food and/or space. There is a competition for attachment place and food between sessile sestonfeeders Balanus improvisus, Mytilus edulis (sea forms) and Dreissena polymorpha (brackish water form) in the Pernu Bight. Salinity is the main factor on which the result of competition depends: the increase of salinity is favorable for two sea forms and does not for zebra mussels (Jarvekiulg 1979).
Habitat change. Some habitats, e.g., secondary hard bottoms (underwater constructions) seem to be rather open everywhere to alien fouling organisms. Here Balanus can increase the area and volume available for associated macro and meiofauna, and enhance detritus-based food chains by supplying their habitat with particulate detritus. Empty shells of the barnacle serve as new microhabitats for small annelids, crustaceans and chironomids. microscale habitat alterations are known to facilitate colonisation of substrate-specific species (Gollach, Leppäkoski 1999; Weidema 2000).
Food-prey for native species. Mytilus edulis can filter from the bottom layer Balanus larvae (Jarvekiulg 1979).
Community dominance - quantitative changes in community structure. Investigated epibenthic communities of the Southern Baltic are strongly dominated by Balanus improvisus (Chojnacki, Ceronik 1997). In dence populations of B. improvisus, assotiated species such as midge larvae, copepod crustaceans and juvenile bivalves increase compared to adjacent sites without crusts (Leppäkoski 1999).
Benthic-pelagic interaction. Filter feeding barnacle transfer organic material from the watermass to the sediment (biodeposition). This provides an important source of material to the benthic environment, and the organisms that live there, including the important detritus food chain (Weidema 2000).
Accumulation of toxic substances. In a preliminary biomonitoring study, accumulated trace metal concentrations (Cu, Zn, Fe, Cd, Pb, Mn, Ni) have been measured in the mussel Mytilus trossulus and the barnacle Balanus improvisus collected in the Gulf of Gdansk, Poland in 1998. Analysis of covariance has shown significant geographical and temporal differences in the local bioavailabilities of trace metals to mussels and barnacles, as reflected in the concentrations of accumulated trace metals. It is concluded that the mussel and barnacle are suitable biomonitors to employ in programmes designed to assess changes in metal pollution in the Gulf of Gdansk, one of the most metal polluted parts of the Baltic Sea, due to the outflow of the River Vistula (Rainbow et al. 2000).
 
 

LIKELY IMPACT ON USES/RESOURCES AND HUMAN HEALTH

Aquaculture. Fouling of blue mussels and oysters. Fouling of cages (Leppäkoski 1999).
Aquatic transport. Another area where fouling causes problems are on underwater constructions and ships' hulls. The application of anti-fouling paints does not only incur an economic cost, but also causes substantial negative effects on the marine environment (Leppäkoski 1999; Weidema 2000).
Fisheries. Can interfere with fisheries, by reducing fish production by influencing the food web of commercial fish species, it is so called dead-end organism that is hardly consumed by fish (Gollach, Leppäkoski 1999).
Tourism/Human health. Sharp shells on the beach may cause tourists’ injuries (Leppäkoski 1999).
Water abstractions. Fouling can cause technical problems and economic loss to installations such as power plants. In an investigation of plants along the Finnish coast it was found that the Bay barnacle was causing problems in plants all along the coast as far north as Vaase in the northern part of the Bothnian Sea (Leppäkoski 1999; Weidema 2000).
Water quality. The increase in biodeposition and mechanical trapping of organic material caused by the Bay barnacle may result in increasing eutrophication of semi-enclosed systems. On the other hand, the "cleansing" of the water mass will decrease the outflow, or "loading", of organic material to adjacent water areas (Leppäkoski 1999; Weidema 2000).

REFERENCES

  1. Barien J. 2002. Genotoxic impacts in Klaipeda Marine port and Butinge oil terminal areas (Baltic Sea). Marine Environmental Research, Elsevier Science Ltd., Vol. 54 (3-5): 475-479.
  2. Birshtain J. A., Vinogradov L. T., Kondakov N. N., Kun M. S., Astakhova T. V.,Romanova N. N. 1968. The Atlas of Caspian Sea invertebrates. Moscow, “Pishevaja promyshlennost”, 415 p. (in Russian).
  3. Chojnacki J.C., Ceronik J. 1997. Artificial reefs in the Pomeranian Bay (southern Baltic) as biofiltration sites. Proceedings of the 13th Baltic Marine Biologists Symposium, Jurmala, Latvia, August 31 - September 4, 1993. Institute of Aquatic Ecology, University of Latvia, Riga (Latvia): 169-172.
  4. Furman E.R., Yule A.B.1990. Self-fertilisation in Balanus improvisus Darwin. Journal of Experimental Marine Biology and Ecology, Vol.144 (2-3): 235-239.
  5. Gollach S., Leppäkoski E.1999. Initial Risk Assesment of Alien Species in Nordic Coastal Waters. Nord 1999:8 : 245 p.
  6. Gruszka P. 1999. The River Odra estuary as a gateway for alien species immigration to the Baltic Sea basin. Acta hydrochim. hydrobiol., Vol. 27 (5): 374-382.
  7. Hayward P. J., Ryland J. S. 1995. Handbook of the Marine Fauna of North-West Europe. Oxford University Press, 800 p.
  8. Jansson K. 1994. Alien Species in the Marine Environment. Introductions to the Baltic sea and the Swedish West Coast. Solna, Swedish Environmental Protection Agency: 68 p.
  9. Jarvekiulg A. 1979. The bottom fauna of the eastern part of the Baltic Sea. Tallinn, “Valgus”, 382 p. (in Russian).
  10. Leppäkoski E. 1999. Balanus improvisus (Darwin 1854), Balanidae, Cirripedia. In: Exotics across the ocean. Case histories on introduced species: their general biology, distribution, range expansion and impact. Published by University of Kiel, Germany, Department of Fishery Biology, Institute for Marine Science: 49-54.
  11. Olszewska A. 2000. Mya arenaria L., a new and unusual substratum for Balanus improvisus Darwin. Oceanologia, 42 (1): 119–12.
  12. Rainbow P.S., Wolowicz M., Fialkowski W., Smith B.D., Sokolowski A. 2000. Biomonitoring of trace metals in the Gulf of Gdansk, using mussels (Mytilus trossulus) and barnacles (Balanus improvisus). Water Research, 34 (6): 1823-1829.
  13. Weidema I.R. 2000. Introduced species in the nordic countries. Nord 2000, 13: 242p.