Plankton Safari

What Is Plankton?

Plankton are the diverse collection of organisms that live in large bodies of water and are unable to swim against a current. The individual organisms constituting plankton are called plankters. They provide a crucial source of food to many small and large aquatic organisms, such as bivalves, fish and whales.


Planktonic organisms include bacteria, archaea, algae, protozoa and drifting or floating animals that inhabit—for example—the pelagic zone of oceans, seas, or bodies of fresh water. Essentially, plankton are defined by their ecological niche rather than any phylogenetic or taxonomic classification.


Though many planktonic species are microscopic in size, plankton includes organisms over a wide range of sizes, including large organisms such as jellyfish. Technically the term does not include organisms on the surface of the water, which are called pleuston—or those that swim actively in the water, which are called nekton. (Wikipedia)


The word “plankton” was coined by German zoologist Victor Hensen (1835–1924). Hensen is also celebrated as the father of biological oceanography. In his time, the discipline of “Biological Oceanography” had not yet been created nor named. 


Hensen made in above contribution two “world-shaking” statements:

Those two terms were  introduced to the world in his 1887 paper published in Wissenschaftliche Meeresuntersuchungen (Scientific Marine Investigations). Titled ueber die bestimmung des planktons oder des im meere treibenden materials an pflanzen und thieren (about the determination of the plankton or the floating material on plants and animals)


Wissenschaftliche Meeresuntersuchungen
He coined the expression PLANKTON (see start of page 1 below). In a footnote he acknowledged the help of his colleague, Professor Foerster, who created the name Plankton from the Old Greek for “floating about.” He basically defined what the aim of “biological oceanography” should be. Hensen recognized that in terrestrial systems data were gained concerning the local productions of grass and grain per unit space. The data were then set in relationship to the amount of people and animals living in the same area. Hensen argued that one should be able to estimate similarly how many fish an area of ocean can produce based on the measured concentrations of nutrients and the available biomass of plankton.

My translation is not word by word but rather should convey the meaning of Hensen’s text. Additionally, the German language has experienced some changes in grammar and spelling since his days.

ueber die bestimmung des plankton’s oder des im meere treibenden materials an pflanzen und thieren 

Plankton are the diverse collection of organisms that live in large bodies of water and are unable to swim against a current. The individual organisms constituting plankton are called plankters. They provide a crucial source of food to many small and large aquatic organisms, such as bivalves, fish and whales.


Planktonic organisms include bacteria, archaea, algae, protozoa and drifting or floating animals that inhabit—for example—the pelagic zone of oceans, seas, or bodies of fresh water. Essentially, plankton are defined by their ecological niche rather than any phylogenetic or taxonomic classification.


Though many planktonic species are microscopic in size, plankton includes organisms over a wide range of sizes, including large organisms such as jellyfish. Technically the term does not include organisms on the surface of the water, which are called pleuston—or those that swim actively in the water, which are called nekton. (Wikipedia)


The word plankton was coined by German zoologist Victor Hensen (1835–1924). Hensen is also celebrated as the father of biological oceanography. In his time, the discipline of “Biological Oceanography” had not yet been created nor named. Hensen made in above contribution two “world-shaking” statements:


The word was introduced in his 1887 paper published in Wissenschaftliche Meeresuntersuchungen (Scientific)

Wissenschaftliche Meeresuntersuchungen

He coined the expression PLANKTON (see start of page 1 below). In a footnote he acknowledged the help of his colleague, Professor Foerster, who created the name Plankton from the Old Greek for “floating about.” He basically defined what the aim of “biological oceanography” should be. Hensen recognized that in terrestrial systems data were gained concerning the local productions of grass and grain per unit space. The data were then set in relationship to the amount of people and animals living in the same area. Hensen argued that one should be able to estimate similarly how many fish an area of ocean can produce based on the measured concentrations of nutrients and the available biomass of plankton.

My translation is not word by word but rather should convey the meaning of Hensen’s text. Additionally, the German language has experienced some changes in grammar and spelling since his days.


ueber die bestimmung des plankton’s oder des im meere treibenden materials an pflanzen und thieren

The word "plankton" was coined by German zoologist Victor Hensen (1835–1924). Hensen is also celebrated as the father of biological oceanography. In his time, the discipline of “Biological Oceanography” had not yet been created nor named. Hensen made in above contribution two "world-shaking" statements:


He coined the expression PLANKTON (see start of page 1 below). In a footnote he acknowledged the help of his colleague, Professor Foerster, who created the name Plankton from the Old Greek for "floating about." He basically defined what the aim of "biological oceanography" should be. Hensen recognized that in terrestrial systems data were gained concerning the local productions of grass and grain per unit space. The data were then set in relationship to the amount of people and animals living in the same area. Hensen argued that one should be able to estimate similarly how many fish an area of ocean can produce based on the measured concentrations of nutrients and the available biomass of plankton.

My translation is not word by word but rather should convey the meaning of Hensen’s text. Additionally, the German language has experienced some changes in grammar and spelling since his days.


ueber die bestimmung des plankton's oder des im meere treibenden materials an pflanzen und thieren

Start of page 1 (English):

Since the cutting-edge research of JOHANNES MUELLER, suspended matter in the oceans, which to date is named “Auftrieb” (floating stuff), enjoys much attention by zoologists and botanists. “Auftrieb” is captured from the water with fine-mesh nets and is not only interesting for its systematics and its morphologies, but also, without a doubt, for its important role in the cycling of nutrients within the ocean environments.


It is the goal of this contribution to investigate this cycling of nutrients more closely. However, the expression “Auftrieb” does not describe the floating matter sufficiently. I prefer to call this material “Halyplankton”. Since this contribution is only concerned with the oceans I will use the shorter expression “Plankton”. I define that plankton is comprised of all particles and materials, which float in the water column, no matter whether they occur in the upper or deeper layers of the water column, or whether they are alive or dead.

On page 2 (English):

I guess that plankton can grow anywhere in the oceans. It consists of live nutrition for others and it seems to be an excellent source of nutrients.

To determine the capacity of this source of nutrients was the goal of my investigations. Already in 1867, I argued before the “preussischen Landrat” (legislative of Prussia) that one needs scientists to investigate the oceans to further our knowledge of the fisheries. At that time, I thought that one needs to know the (primary and secondary) production of the oceans and then relate it to the fisheries. Later, as member of the newly constituted scientific commission, I first researched the local yields of fish and the sizes of fishing grounds off the coasts of Germany. Then, I looked at the historical data of fish yields and estimated the average yields of the different coastal areas. Lastly, I tried to determine on the basis of the counts of floating fish eggs the population density of fishes per area. This last step convinced me fully that it will be possible, and that it will be even imperative, to investigate the primary (and secondary) production, which forms the basic food for the animals of the oceans.

This task necessitates a quantitative estimation of the primary (and secondary) production. I am guided in my opinion by the following argument. In terrestrial systems one gets data on the yearly production of grass or grain per area land, and on the amount of people and domesticated animals living within these areas. However, no such data are gained from other living (eco-) systems. The systemacists describe one or the other species as abundant or rare; they supply, however, no counts per unit space. Nevertheless, it is remarkable that even with such episodic data one may be able to estimate in general the density of animals. It seems that the reason for less accounting in terrestrial areas lies in the differences in structure when compared to the rather enclosed areas of land people and domestic animals inhabit.

However, I perceive matters to be much more manageable on the surface of the oceans. Salinity, light levels, winds and water movements are over large areas the same. Physical disturbances, such as waves and currents, only help to mix more thoroughly the water and its plankton so that estimates may be even more generally applicable.

Start of page 1 (German):

Das mit dem Namen “Auftrieb” bezeichnete Material, welches von Zoologen und Botanikern, seit den bahnbrechenden Arbeiten von JOHANNES MUELLER, so vielfach untersucht worden ist und mit feinem durchlaessigen Netz gefischt wird, hat, neben seinem Interesse fuer Systematik und Anatomie, ohne Zweifel fuer den ganzen Stoffwechsel des Meeres eine grosse Bedeutung.


Diese Arbeit versucht es, dem bezueglichen Stoffwechsel naeher zu treten. Es zeigt sich, dass der Name: Auftrieb nicht genuegend umfassend und bequem ist, so dass ich es vorgezogen habe dies Material mit dem Namen Halyplankton zu belegen; da hier jedoch nur vom Meere die Rede ist genuegt der kuerzere Ausdruck Plankton. Ich verstehe darunter Alles was im Wasser treibt, einerlei ob hoch oder tief, ob todt oder lebendig.

On page 2 (German):

Das Plankton kann im Allge- meinen wohl ueberall im Meere wachsen, es gewaehrt lebendige Nahrung, und scheint deshalb eine vorzuegliche Quelle der Nahrungsstoffe zu sein.

Dieser Stoffquelle nachzugehen ist die Aufgabe, zu welcher ich im Verlauf meiner Unter- suchungen gefuehrt worden bin. Schon als ich 1867 im preuss- sischen Landtag fuer die Herbeiziehung wissenschaft- licher Untersucher zur Erforschung des Meeres im Interesse der Fischerei eintrat, schwebte mir der Gedanke vor, dass man nur dann richtige Massnahmen im Interesse der Fischerei werde aufzufinden vermoegen, wenn man in der Lage sei, sich ein Urtheil ueber die Ertragsfaehigkeit des Meeres zu bilden. Als Mitglied der bezueglichen wissenschaft- lichen Kommission habe ich dann zunaechst die Staerke und die Ausdehnung der Befischung der deutschen Kueste festgestellt, darauf, mit Huelfe der Verfolgung der Ergebnisse einiger Fischereien, die mittlere Groesse des Ertrages bestimmter Kuestenstrecken zu bestimmen gesucht, zuletzt endlich habe ich mich bemueht, durch Zaehlungen der treibenden Fischeier eine Vorstellung ueber die Menge der, auf dem entsprechenden Gebiet befindlichen Fische ein annaeherndes Urtheil zu gewinnen. Letztere Unter- suchungen haben mich endlich zu der Ueberzeugung gefuehrt, dass es nothwendig und moeglich sei, der Urnaehrung der Meeresthiere naeher zu treten.

Diese Aufgabe erfordert quantitative Bestimmung der Urnahrung; die Moeglichkeit, solche Bestimmungen zu machen, ergiebt sich aus folgender Betrachtung. Auf dem Lande werden Massangaben gewonnen ueber die jaehrliche Produktion an Gras und Getreide, an Menschen und gezaehmten Thieren; bezueglich der uebrigen belebten Welt scheinen derartige Angaben nicht gewonnen werden zu koennen; die Systematiker bezeichnen zwar diese oder jene Art als gemein oder selten, jedoch es ist damit irgend ein bestimmtes Mass nicht ge- geben; immerhin ist bemerkens- wehrt, dass solche Angaben die Erfahrung zu grunde liegt, wie sehr vereinzelte Beobachtungen einen Schluss fuer sehr ausgedehnte Strecken zu machen erlauben. Der Grund, weshalb fuer die belebten Wesen der freien Natur eine Zaehlung nicht eintreten kann, liegt in der grossen Verschiedenheit der Lebens- bedingungen innerhalb von immerhin recht beschraenkten Landflaechen.

An der Oberflaeche des Meeres liegen die Dinge in dieser Beziehung weit guenstiger; Salzgehalt, Licht, Luft und Bewegung sind im Ganzen ueberall die gleichen; Stoerungen, wie Wellen und Stroemungen werden nur zu einer vollkommeren Mischung des Planktons fuehren koennen, so dass hier eine Verall- gemeinerung der Befunde die groesseste Berechtigung zu haben scheint.