The marine macroalgae of Helgoland (North Sea): an annotated list of records between 1845 and 1999

The earliest known records of marine macroalgae from Helgoland (German Bight, North Sea) date from the mid-19th century. Since then, 274 marine macroalgal species have been reported: 77 species of Chlorophycota, 100 species of Phaeophycota and 97 species of Rhodophycota. Additionally 11 species were only recorded as drift and 51 species as doubtful for Helgoland. The remains of the herbarium of Paul Kuckuck, the first curator for botany at the Helgoland Biological Station between 1892 and 1914, are still located there and consist of 173 macroalgal species from Helgoland. On comparing this 100-year-old herbarium and other old sources with recent macroalgal records, it became clear that changes in species composition have occurred. After World War II, several species such as Arthrocladia villosa, Corynophlaea crispa, Cutleria multifida, Eudesme virescens, Mesogloia vermiculata, Sporochnus pedunculatus, Antithamnion cruciatum, Apoglossum ruscifolium, Chondria dasyphylla, Helminthora divaricata, Jania rubens and Osmundea ramosissima were not found again. Other species such as Dictyota dichotoma, Leathesia difformis, Stictyosiphon soriferus, Helminthocladia calvadosii and Scinaia furcellata became very rare. Significantly, perhaps, most of these species have a heteromorphic life history with the appearance of the macroscopic phase restricted to (spring and) summer. Many new species of green algae were recorded for Helgoland after 1959, due to new substrata and the research activities of Peter Kornmann, curator for botany after 1959, and Paul-Heinz Sahling his technical assistant. Introductions of species during the considered time period were: Bonnemaisonia hamifera, Codium fragile, Mastocarpus stellatus and Sargassum muticum. Type material of the following species is located at the Marine Biological Station at Helgoland: Mikrosyphar porphyrae, Porphyra insolita and Ulva tenera. Received in revised form: 22 May 2000 Electronic Publication     

Die Entwirrung desBotrytella(Sorocarpus)-Komplexes (Ectocarpaceae,Phaeophyta)

Sorocarpus Pringsh. is a later synonym forBotrytella Bory. Four species of the genus are known from northern European coasts. Three of them are found at Helgoland (North Sea), type locality of bothBotrytella uvaeformis (Pringsh.) andB. reinboldii (Reinke). A third species, most frequently seen, still remains unnamed. Plants of similar habit, however, have been described from Japan. The type species for the genus,Botrytella micromora Bory, was originally published asEctocarpus siliculosus β.uvaeformis by Lyngbye. A sample from Danish waters proved to be identical with it. In a previous paper (Kornmann & Sahling, 1984), the life history of two species was studied and the investigation is now extended to include the other two, demonstrating the conformity of the four species with the genus characters as to morphological and developmental features.      

Meeresalgen von Helgoland: Ergänzung

Complementary to a previous publication (Kornmann & Sahling, 1977), this investigation deals mainly with microscopic algae occurring in the rocky littoral of Helgoland island (North Sea). Based on the results obtained from cultivation experiments, the heterogeneousUlvella-complex of Dangeard has been rearranged and partly included in a new genusStromatella, andPlanophila respectively. The life history ofChlorocystis cohnii proved to be heteromorphic, the zygotes developing into a Codiolum-sporophyte. Also inHalochlorococcum marinum, some of the biflagellate swarmers give rise to Codiolum-like cells.Chlorocystis andHalochlorococcum, up to now members of the Chlorococcales, are incorporated into the new Codiolophycean order, Chlorocystidales. Three newHalochlorococcum species are described, the epiphytic“Chlorochytrium” moorei also being combined with this genus. Supplementary observations on some crustose red algae from transparent substrates are included in this study, as well as findings of some species not previously reported for the Helgoland area.     

Guest research facilities at the Biologische Anstalt Helgoland: Past and present

The Biologische Anstalt Helgoland (BAH) offers unique possibilities for research and education in marine sciences in the southern part of the North Sea. Besides its own research duties, the Institute provides research facilities and technical assistance for guest scientists, assists in the teaching and education of university student groups, and conducts its own courses. The Institute further supplies universities and research institutions on the mainland with marine organisms. The marine station on Helgoland has 14 laboratories, with a total of 32 working places available for guest scientists. The Wadden Sea Institute in List on the island of Sylt offers 6 laboratories with a total of 18 working places. Furthermore, laboratory classrooms are located on Helgoland and in List for 50 and 20 participants, respectively. For the convenience of the guest researchers staying at the BAH, guest-houses are run on Helgoland (Arthur-Hagmeier-Haus, Wilhelm-Mielk-Haus) und in List (Adolf-Bückmann-Haus). Guest researchers have been welcome since the founding of the Institute in 1892. Heincke gave a brief report on the activities of the first visitors from 1892 to 1897. Only sporadic reports are available for the first 60 years of this century. Guest scientists and their activities have only been recorded in detail in the annual reports of the BAH since 1962. The number of researchers and the length of their visits have increased continuously since 1962. The research facilities on Helgoland, in List and Hamburg have been modernized during the last 20 years. In 1971, four modern laboratories for guest researchers could be opened on Helgoland with financial support of the German Research Foundation (DFG). The number, of guest researchers in List and Hamburg increased after the completion of new buildings in 1979 and 1982. The recent increase in research activities by guest scientists is due to numerous students, from many different universities, using the superb research facilities to do their Masters thesis, or Ph.D. Guest researchers and students either perform their own research or cooperate with scientists of the BAH.     

Phytoplankton and nutrients in the Helgoland region

During recent decades, phytoplankton stock on the one hand and inorganic nutrients (P and bound N) on the other have increased considerably in the southern North Sea, as demonstrated at a permanent station (since 1962) near the island Helgoland. This correlation between phytoplankton and inorganic P and N need not have anything to do with causality; exceptional algal blooms have been observed and reported in the literature since in the 19^th century. Furthermore, these increases (four-fold for phytoplankton and two-fold for nutrients) are in the same range as the fluctuations from year to year under different hydrographical conditions. A detailed investigation carried out in 1981 demonstrated the presence of a slowly growing phytoplankton population. Starting with a considerable stock of flagellates in spring, it reached a peak in cell numbers over a long reproduction period which contrasted with the normal duration of a spring bloom of diatoms. These processes were not related to a limited production by P or N. A considerable concentration of these nutrients was permanently available in the form of inorganic compounds. The total amount of nutrients surpassed by far the portion incorporated in the phytoplankton. This is a consequence of the fact that small organisms have a high metabolic rate. Therefore, the relation between stock and production (daily production ≈stock) is completely different from that known e.g. in agriculture. The nutrients exist during the vegetation period mainly in the form of dissolved organic matter that is accessible to plankton. The great dynamics of this system, including a phase shifting during the year between inorganic P, N, Si, and production, indicates the significance of permanent and fast remineralization. Calculations demonstrate that the natural nutrient content of seawater normally satisfies the demands of phytoplankton present in the North Sea area under study. Only in the more productive coastal region (salinity<30 associated with fresh water run-offs of low nutrient content — an unrealistic assumption in the German Bight) might some limitation be observed. For diatoms, silicate may represent a critical component, but a high dynamic force exists in the presence of small Si concentrations. Therefore, a lack of silicon must not represent any limitation; however, knowledge on the silicon system is insufficient up to now. Dedicated to Dr. Dr. h. c. Peter Kornmann on the occasion of his eightieth birthday.     

Ecological long-term research at Helgoland (German Bight,North Sea): retrospect and prospect—an introduction

This paper summarizes and evaluates ecological long-term observations at the island of Helgoland (German Bight, North Sea). It is an introduction to a series of seven contributions to an issue of Helgoland Marine Research (vol. 58, no. 4) dealing with observations on the physico-chemical environment and the local biota (pelagic bacteria, phytoplankton, zooplankton, macroalgae, macrozoobenthos). More than 150 years of research at Helgoland (at the Biologische Anstalt Helgoland, BAH, since 1892), and particularly the Helgoland Roads time-series which started in 1962, has provided a multitude of data which represents a valuable basis for analysing past changes, evaluating the present status and predicting future changes in ecosystem parameters. Predicting the consequences of the recent rapid ecological change on regional and global scales requires increased efforts of focus on long-term ecological observations. Future efforts in this field will rely on the application of innovative advanced technology and on the concerted activities of a large number of institutions which only collectively can establish the large-scale patterns of temporal and spatial change in ecosystem functions.     

Studies on sexual compatibility betweenEctocarpus siliculosus (Phaeophyceae) from Chile and the Mediterranean Sea

Clonal isolates of the brown algaEctocarpus siliculosus (Ectocarpales) originating from Naples (Mediterranean Sea) and southern Chile were compared in laboratory culture studies. The two isolates showed distinctly different morphological characters, but very similar details of life history and sexual reproduction. Gametes are sexually compatible; hybrid zygotes are formed and sporophytes develop, which are fertile on the basis of mitotic spores. However, unilocular sporangia were abortive, indicating segregational sterility caused by chromosomal mismatch during meiosis. Although the biological species concept in a strict sense does not apply, and appreciable morphological variability exists in this cosmopolitan taxon, local populations are considered as representatives of the same species. Dedicated to Dr. Dr. h. c. Peter Kornmann on the occasion of his eightieth birthday.     

Helgoland (Germany): hemogenetic study of an island population

24 haemogenetic markers (5 erythrocyte antigenes, 6 polymorphisms of serum proteins, 12 polymorphisms of red cell enzymes) had been studied in up to 80 individuals from the island of Helgoland (Germany). The cluster analysis separates clearly the Helgoland sample from the neighbouring populations as well as from European standard data. This special position is interpreted partly by genetic peculiarities developed in the course of time, partly as a consequence of genetic drift.     

Beobachtungen zum postembryonalen Wachstum vonTrichodamon froesi Mello Leitao (Amblypygi,Arachnida)

Zusammenfassung Das positive allornetrische Wachstum von Pedipalpen und Laufbeinen vonT. froesi wird demonstriet. Die Zahl der Tibialdornen an der Tibia wird vom vierten Stadium an reduziert bis nur noch die Dornen übrigbleiben, die die terminale Greifschere bilden. Das 1. Beinpaar wächst isometrisch, und die Zahl der Fühlerbeinsegmente bleibt vom 2. Stadium an nahezu konstant. Es wird vorgeschlagen, die Damoniae Simon 1936 und Phrynichinae Simon 1892 in der Familie Phrynichidae zusammenzufassen.

---

Postembryonic growth inTrichodamon froesi mello leitao (Amblypygi, Arachnida)

Summary Positive allometric growth of pedipalps and walking legs is demonstrated inT. froesi. From the fourth instar onward, the number of spines on the pedipalp tibia is reduced, and finally only those which participate in the formation of the pincers remain. The first legs grow isometrically, and the number of antenniform leg segments remains nearly constant from the second instar onward. It is suggested that the subfamilies Damoninae Simon 1936 and Phrynichinae Simon 1892 belong to a single family, the Phrynichidae.

     

Verbreitung und Ökologie derVaucheria-Arten (Tribophyceae) des Elbe-Ästuars und der angrenzenden Küste

From the Elbe estuary and the adjacent North Sea coast, 19 species ofVaucheria are on record. Their horizontal and vertical distribution pattern as well as their association with macrophyte communities are described. With regard to ecological salinity tolerance and distribution below or above mean high water, 7 ecological groups ofVaucheria species are defined. Dominating species which form extensive algal mats in the upper eulittoral zone areVaucheria compacta var.dulcis (freshwater and oligohalinic section of the estuary),V. compacta var.compacta (mesohalinic section) andV. velutina together withV. subsimplex (polyhalinic and euhalinic section). The rare speciesV. vipera is recorded for the first time from the German coast.

---

---

Herrn Dr. Dr. h. c. Peter Kornmann zum 80. Geburtstag gewidmet.

---

Adressat für Sonderdruckwünsche: Prof. Dr. L. Kies.     

Five scientists on excursion — a picture of marine biology on Helgoland before 1892

Five scientists on excursion — a picture of marine biology on Helgoland before 1892. The picture, of which several variant poses with minor differences exist, is a photograph taken on Helgoland in September, 1865. The original is to be found in the collections of the Ernst-Haeckel-Haus in Jena. The photograph shows only a few objects and fewer persons, but they are arranged like a bouquet: in front, collecting vessels; behind, grouped around a table, five scientists, Dohrn, Greeff, Haeckel, Salverda, Marchi. They hold up their catching nets like insignia, identifying their basic activity. This photograph is a unique document for the marine biological research on Helgoland before 1892. Furthermore, it illustrates a time and place for the birth of the idea of establishing the world's most famous marine biological station, the Stazione Zoologica di Napoli.     

Kurzzeitige Veränderungen hydrographischer Faktoren und der Sestonkomponenten in driftenden Wassermassen in der Helgoländer Bucht

Zusammenfassung 1. In der Helgoländer Bucht wurden vor der Elbe- und Eidermündung sowie bei Helgoland driftende Wassermassen 4–8 Stunden lang untersucht. Dabei wurden in etwa halbstündigen Zeitabständen Vertikalserien von Wasserproben entnommen und Salzgehalt, Temperatur, Trübung und Sestongewicht bestimmt sowie Phytoplankton gezählt (Abb. 2–4).2. Lediglich das auflaufende Wasser bei der Driftstation Außeneider blieb hydrographisch unverändert; nur hier waren die Voraussetzungen für die Messung kurzzeitiger Veränderungen des Partikelgehalts gegeben. Das unbewegliche Plankton (Diatomeen) zeigte nicht den raschen Abfall der Konzentration mit dem Nachlassen des Gezeitenstroms wie das Sestongewicht und die Trübung.3. Die Verfolgung driftenden Wassers bei Helgoland ließ erkennen, daß durch die besonderen Gezeitenstromverhältnisse Wassermassen mehrmals um die Insel kreisen und die Helgoland-Reede passieren können.4. Diese Untersuchungen wie auch veröffentlichte Ergebnisse von Messungen der horizontalen Diffusion im Meerze zeigen, daß Untersuchungen der Veränderungen innerhalb einer einzelnen Planktonpopulation im Laufe von mehreren Tagen in der Helgoländer Bucht eine aufwendige Gemeinschaftsarbeit erfordern.

---

Short-term variations of hydrographical factors and seston components in drifting water masses in Helgoland Bight

In Helgoland Bight (Inner German Bight, North Sea) drifting water masses were investigetad at 3 stations for 4–8 hours during August and November, 1968. Measurements of salinity, temperature, turbidity and seston weight were made and phytoplankton was counted in vertical series of water samples taken at about 30 — minute intervals. Only the water at drifting station Außeneider remained hydrographically unchanged during the investigation. The concentration of non-motile phytoplankton (diatoms) did not decrease with the slowing down of tidal current, whereas seston weight and turbidity decreased rapidly. Drift-cross tracking of the water at Helgoland Roads revealed that the water masses may circle around the island several times. Published results on horizontal diffusion and the present data indicate that measurements of changes within a plankton population over several days in Helgoland Bight require elaborate teamwork.

---

---

Herrn Prof. Dr.J. Krey zum 60. Geburtstag in Verehrung gewidmet.     

Schweingruber’s cosmos of inspiration

Born 29^th February 1936 near Bern, Switzerland, Fritz Hans Schweingruber worked as a teacher until 1965, obtained a PhD in botany from the University of Basel in 1972 (where he also obtained a Professorship in 1976), and started his lifelong career at the Swiss Federal Research Institute WSL in Birmensdorf right afterwards. Fritz developed a dendrochronological network across much of the Northern Hemisphere, expanded wood (xylem) science beyond forests, implemented wood anatomical techniques into dendroecology and paleoclimatology, and enthusiastically trained thousands of students, of which hundreds remained actively involved in the still emerging field of tree-ring research. Though Fritz died 7^th January 2020 after an extraordinary academic career, his intellectual legacy will continue to inspire scholars around the world.     

Morphogenesis and generic concepts in coralline algae — a reappraisal

In coralline algae, anatomy has long been used for generic definition, in addition to reproductive structures. Coralline anatomy is here analysed according to its two main components: cell behaviour and morphogenesis. The meristems and thir function are explained and the main types of organization are examined in an evolutionary context. Emphasis is given to ontogenetical data such as the occurrence of metamorphosis and progressive development in some species of theLithophyllum complex, which have raised difficulties for generic definitions in the past. Consequently, a certain number of terms (epithallus, hypothallus, perithallus) are clarified and some of them restricted in relation to their morphogenetic significance. As a consequence of this clarification, evolutionary groups are defined and within them parallel phylogenetic lines appear as continuums along which genera are morphogenetic steps. Dedicated to Dr. Dr. h. c. Peter Kornmann on the occasion of his eightieth birthday.     

Zur Populationsgenetik der sauren Phosphatase der Erythrocyten (E C 3.1.3.2): Phänotypen-und Allelhäufigkeiten in Südwestdeutschland

Summary Within an population sample of 300 individuals of Southwestern Germany the red cell acid phosphatase polymorphism is investigated. Gene frequency estimates are: P^a=0.31, P^b=0.643, P^c=0.047.

---

---

Direktor: Prof. Dr. med. Dr. H. Baitsch

---

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.     

Die GattungTrilobodrilus (Archiannelida,Polychaeta) von der deutschen Nordseeküste

Zusammenfassung 1. Die beiden im deutschen Küstenraum lebenden Archianneliden-Arten der GattungTrilobodrilus werden vergleichend dargestellt.2.T. heideri Remane aus dem Sublitoral von Helgoland erhält eine ergänzende Beschreibung.3.T. axi nov. spec. wird als neue Art aus dem Eulitoral von Sylt beschrieben.4. Die Artidentität der bisherigen Funde vonT. heideri wird diskutiert.5. Es wird auf die weitgehende Übereinstimmung vonT. heideri undT. nipponicus Uchida & Okuda hingewiesen.

---

The genustrilobodrilus (archiannelida, polychaeta) from the German coast of the North Sea

A comparison betweenT. heideri Remane from the sublittoral zone near the island Helgoland andT. axi nov. spec. from the sandy eulittoral zone of the island Sylt is presented. The two species, having very similar appearance, are separated by the size, the form of the prostomium, the number of segments and the form of the glands in the epidermis. It is most probable that allT. heideri hitherto described for eulittoral habitats are identical withT. axi.

     

Beitrag zur Genetik der Erythrocyten-Phosphoglucomutase

Summary Blood samples from 515 unrelated individuals and from 41 families with 80 children living in Hessen (Germany) were examined for erythrocyte phosphoglucomutase (PGM₁) polymorphism. The gene frequences especially fit well with those obtained in Berlin and Danmark. The family studies verify the supposed way of heredity without any exception.

---

---

Direktor: Prof. Dr. W. Spielmann     

Zur formalen Genetik des Duffy-Systems

The formal genetics of the Duffy-polymorphism was examined, using reagents Anti-Fy(a) and Anti-Fy(b). Our family series comprises 247 unselected families from the southwestern part of Germany with 459 children; extramarital children are excluded from this investigation. The results agree with the hypothesis 3 alleles Fy^a, Fy^b, Fy at an autosomal locus.

---

---

Direktor: Prof. Dr. Dr. H. Baitsoh

---

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.