What are zooplankton, and why do they matter?
The zooplankton community is an important element of the aquatic food chain. These organisms serve as an intermediary species in the food chain, transferring energy from planktonic algae (primary producers) to the larger invertebrate predators and fish who in turn feed on them. Zooplankton are highly sensitive to changes in aquatic ecosystems.
What are the types of zooplankton?
Zooplankton
- Characteristics of zooplankton. They are able to live in both fresh and salt water. ...
- Types of zooplankton. ...
- Zooplankton feeding. ...
- Representative species
- Usage of zooplankton. ...
- Importance. ...
How to identify zooplankton?
How to collect and identify plankton
- Select a station. First, keep in mind that zooplankton are most prevalent in lakes, ponds, reservoirs, and any tidal body of water such as tidal streams and rivers, bays, and ...
- Choose a net. The type of net you use will dictate the type of zooplankton you collect. ...
- Collect a sample. ...
- Identify your catch. ...
- Plankton as pets. ...
What is the predator of zooplankton?
The posting of preprints on public servers allows almost immediate dissemination and scientific feedback early in the 'publication' process. Metabolic rate is a trait that can be hypothesized to evolve in response to a change in predation.
What is the most common type of zooplankton?
copepodsA very broad range of animals live their entire lives in the plankton and are referred to as holoplankton. Among these are the copepods, which are small (1-2 mm long) aquatic crustaceans, and are generally the most abundant zooplankton species (Figure 1).
What are the two most common zooplankton?
Two general groups of zooplankton exist: those that remain planktonic throughout their entire life (holoplankton), and those that are larval stages of larger life forms (meroplankton).
What is the common name for zooplankton?
In lakes and ponds, the most common groups of zooplankton include Cladocera and Copepods (which are both micro-crustaceans), rotifers and protozoans.
What are some examples of zooplankton?
Portuguese man o' warForamsCalanus finmarchicusRadiolariaMoon jellyAntarctic krillZooplankton/Representative species
What are the major types of zooplankton?
There are two major types of zooplankton: those that spend their entire lives as part of the plankton (called Holoplankton) and those that only spend a larval or reproductive stage as part of the plankton (called Meroplankton).
Is jellyfish a zooplankton?
Zooplankton include microscopic animals (krill, sea snails, pelagic worms, etc.), the young of larger invertebrates and fish, and weak swimmers like jellyfish. Most zooplankton eat phytoplankton, and most are, in turn, eaten by larger animals (or by each other).
Are crabs zooplankton?
A major category of zooplankton is crustaceans, both the larval form of larger animals such as crabs and shellfish, and smaller, floating crustaceans that are an abundant and critical food source for larger animals.
Is amoeba a zooplankton?
Amoebas are single-celled, eukaryotic plankton. One organelle is called the nucleus.
Is shrimp a zooplankton?
Other crustaceans in the zooplankton include species of opossum shrimps (order The planktonic ecosystem; arrows show the movement of biomass through the food chain. Illustration by Hans & Cassidy. Courtesy of Gale Group. Mysidacea), amphipods (order Amphipoda), and fairy shrimp (order Anostraca).
Is algae a zooplankton?
Zooplankton are small, aquatic microorganisms in the water column that include crustaceans, rotifers, open water insect larvae and aquatic mites. The zooplankton community is composed of both primary consumers, which eat free-floating algae, and secondary consumers, which feed on other zooplankton.
How many zooplankton are there?
Presently, the zooplankton community consists of Cladocera, Copepoda, and Rotifera at ∼200 species.
Is lobster a zooplankton?
Many animals, from single-celled Radiolaria to the eggs or larvae of herrings, crabs, and lobsters, are found among the zooplankton. Permanent plankton, or holoplankton, such as protozoa and copepods (an important food for larger animals), spend their lives as plankton.
Where are zooplankton found?
As a result, zooplankton are primarily found in surface waters where food resources (phytoplankton or other zooplankton) are abundant. Just as any species can be limited within a geographical region, so are zooplankton. However, species of zooplankton are not dispersed uniformly or randomly within a region of the ocean.
Which physical factor influences zooplankton distribution the most?
The physical factor that influences zooplankton distribution the most is mixing of the water column ( upwelling and downwelling along the coast and in the open ocean) that affects nutrient availability and, in turn, phytoplankton production.
What is the role of zooplankton in the aquatic food web?
Through their consumption and processing of phytoplankton and other food sources, zooplankton play a role in aquatic food webs, as a resource for consumers on higher trophic levels (including fish), and as a conduit for packaging the organic material in the biological pump.
Why are zooplankton important?
Since they are typically small, zooplankton can respond rapidly to increases in phytoplankton abundance , for instance, during the spring bloom. Zooplankton are also a key link in the biomagnification of pollutants such as mercury. Zooplankton can also act as a disease reservoir.
What are the metazoan zooplankton?
Important metazoan zooplankton include cnidarians such as jellyfish and the Portuguese Man o' War; crustaceans such as copepods, ostracods, isopods, amphipods, mysids and krill; chaetognaths (arrow worms); molluscs such as pteropods; and chordates such as salps and juvenile fish.
What are macrozoolankton?
Macroscopic zooplankton include pelagic cnidarians, ctenophores, molluscs, arthropods and tunicates, as well as planktonic arrow worms and bristle worms . Zooplankton is a categorization spanning a range of organism sizes including small protozoans and large metazoans.
What is the name of the organism that drifts in the ocean?
Plankton are organisms drifting in oceans, seas, and bodies of fresh water. The word zooplankton is derived from the Greek zoon ( ζῴον ), meaning "animal", and planktos ( πλαγκτός ), meaning "wanderer" or "drifter". Individual zooplankton are usually microscopic, but some (such as jellyfish) are larger and visible to the naked eye .
What is Zooplankton?
Zooplankton is a small aquatic animal of the planktonic community. They are heterotrophic aquatic microorganisms in the water column. The word “zoo” comes from the Greek word for “ animal ” and “ planktos ” which means “ wanderer ” or “ drifter “. They are normally microscopic, even though some of them are larger and can be seen with the naked eye.
What does zooplankton eat?
Zooplanktonic organisms are usually found in the surface water where their kind of food is abundant. They feed on a variety of bacterioplankton, phytoplankton, and even other zooplankton. The majority of zooplanktons are filter feeders that use their feeding appendages to filter particles from the water.
Is zooplankton a producer?
The zooplanktons are not producers, rather, they are the animal-like primary consumers of the plankton community. Zooplanktonic organisms in turn are food for larger secondary consumers like fish. The phytoplankton, on the other hand, is the producer, not zooplankton, they are the tiny plant-like producers of the plankton community.
Types of Zooplankton
Radiolarians are also called radiozoa. They are small protozoans of diameter 0.1-0.2 mm that produce mineral skeletons that are made of silica. This group of zooplankton is found throughout the global ocean. The skeletal remains of these organisms can be found at the bottom of oceans.
Zooplankton adaptation
For plankton to be able to float in the water, they have to develop structural adaptations. Hence, all species of plankton have adaption for floating. Such adaptations include:
Zooplankton Habitat
Certain zooplankton species occupy specific marine habitats. They are uniquely adapted to factors in their habitats such as light, turbulence, temperature, and salinity. The zooplankton species on one side of the Gulf Stream are different from the zooplankton on the other side.
Zooplankton in the food chain
Zooplankton and phytoplankton are key components of marine ecosystems. They actually form the base of trophic levels of most marine food webs. The zooplankton community is a crucial element of the aquatic food chain. They are an intermediary species in the food chain.
What are the different types of zooplankton?
Holoplanktonic zooplankton are freefloating their entire lives and are mostly invertebrates. Flagellated, ciliated, and amoeboid protozoa as well as several species from the animal phyla Cnidaria, Ctenophora, Chaetognatha, Mollusca, Annelida, Urochordata, Echinodermata, and Arthropoda make up the majority of collected organisms.
Where can zooplankton be found?
Zooplankton is found in almost all major fresh and marine water bodies.Many species, however, are restricted to specific territories depending on conditions of light, temperature, salinity, chemical composition, and turbulence. Their range also varies geographically and vertically within the water column. The diversity of zooplankton makes ...
Why are copepods considered zooplankton?
Although generally small, even jellyfish several meters in size are considered zooplankton because they are unable to swim effectively against the current. Copepods are one of the most studied forms and are classified as holoplanktonic zooplankton. Copepods have a segmented body with three distinct sections.
Why is it important to link phytoplankton and zooplankton?
The link between phytoplankton and zooplankton is also important in passing the energy fixed by autotrophs to higher trophic levels of the food chain. Herbivorous zooplankton are eaten by carnivorous zooplankton, other invertebrates, or fish.
Why is it harder for zooplankton to move?
In addition, high salinity and low temperatures increase the viscosity of surrounding water, making it harder for zooplankton to move. Alarger surface area and flattened body form covered by many projections or spines counteracts these obstacles and prevents the zooplankton from sinking.
How do zooplankton increase buoyancy?
Several zooplankton also increase their buoyancy by storing low-density materials, such as certain oils. Small body movements, including the action of flagellae and cilia, also counteract the sinking motion. Vertical Migration. The depth at which zooplankton exist is variable.
What is zooplankton eaten by?
Herbivorous zooplankton are eaten by carnivorous zooplankton, other invertebrates, or fish. The food chain may terminate in the top carnivores that include large fish, birds, and mammals, including humans. Adaptations. Because of their small size, zooplankton are very sensitive to water conditions. Maintaining position in ...
Where are zooplankton found?
Zooplanktons are near the bottom of the marine food chain and are eaten by a number of other species meaning that microplastics create a risk of contaminating aquatic food chains that in turn has the potential for increasing public exposure to harmful chemicals through seafood.
How big is a zooplankton?
The zooplankton are commonly divided into several size classes, that is, microzooplankton (<200 μm), mesozooplankton, (0.2–2 mm), macrozooplankton (2–20 mm), and megazooplankton (>20 mm). The relative contributions of these size classes to total phytoplankton biomass can vary substantially. In terms of numbers, the most abundant zooplankters in ...
What are the two main terms in the zooplankton biomass equation?
Zooplankton grazing and losses due to natural mortality/consumption by higher predators are the two main terms in the zooplankton biomass equation. Zooplankton has three alternative food sources (the two phytoplankton groups and biogenic particulate material or detritus) grazed with preference that changes dynamically as a function of their relative proportion (Fasham et al., 1990 ). (It should also be noted, however, that the present model parametrization also postulates a selective zooplankton preference for phytoplankton and detritus over cyanobacteria.) Temperature-modulated zooplankton grazing was modeled using a Michaelis–Menten equation and the assimilated fraction of the grazed material fuels growth. In the absence of information to support more complex forms, we selected a linear closure term that represents the effects of a seasonally invariant predator biomass (see Edwards and Yool, 2000 ).
What is zooplankton grazing?
Zooplankton grazing is recognised as the main mechanism by which phytoplankton production is channelled to the top pelagic consumers, within marine systems. However, use of the broad categories of phytoplankton and zooplankton is too simple to illustrate the complexity of herbivore transferences in the plankton food chains, requiring a more realistic analysis on the basis of size categories (Fenchel, 1988 ). The quantification of trophic transferences by size categories is, therefore, fundamental to the establishment of the particular energy pathways and community efficiency, in any system.
Why does zooplankton grow faster in spring?
As water temperatures warm up in spring and summer, zooplankton growth rates are enhanced and biomass can accumulate at faster rates. Also, nutrient supplies to phytoplankton tends to decrease, largely because the main source of nutrients to the estuary, freshwater runoff, often decreases during these drier periods.
What do crustaceans eat?
Larger crustaceans such as hyperiid amphipods and euphausiids (krill) feed on smaller zooplankton and in turn serve as prey for marine vertebrates. Arctic euphausiids are mostly reported at the inflows to the Arctic and in more productive regions, but are almost absent from the central basins ( Lovejoy et al., 2017 ).
How much of the zooplankton is in the Arctic?
These are estimated to account for 80–90% of the zooplankton biomass in the Arctic, with over 150 copepod species among the c. 350 zooplankton species reported for Arctic ( Bluhm et al., 2011 ). Copepods are directly consumed by many fish, some seabirds, and baleen whales ( Darnis et al., 2012 ).
Where are zooplankton found?
HABITAT. At the Savannah River Site, zooplankton are found in freshwater reservoirs, ponds and streams. They are abundant in Carolina bays, wetlands that often dry in the summer and fill with water in the fall. Because the animals are wholly aquatic but often live in habitats that dry temporarily, they are faced with problems related to ...
What is a zooplankton?
Zooplankton Fact Sheet. Zooplankton are microscopic invertebrate animals that swim or drift in water. They are at the base of the food chain, feeding on microscopic plants and being fed upon by aquatic insects, fish and salamanders. Their sizes usually range from one-tenth of a millimeter to four millimeters, which is smaller than the head of a pin.
Why are zooplankton found in Carolina bays?
Because zooplankton have low migration rates, zooplankton found in Carolina bays provide a good system to study for population and community processes. The community is fairly well contained, and researchers know a direct link exists between what is found in the habitat from year to year. FEEDING. Most zooplankton are filter feeders, using their ...
Why are zooplankton faced with problems?
Because the animals are wholly aquatic but often live in habitats that dry temporarily, they are faced with problems related to the unpredictability of their watery existence. Different types of zooplankton respond to these challenges in various ways.
Where do cladocerans live?
Cladocerans live in nearly all types of freshwater habitats ; they are most abundant in the spring. Adult copepods have long, cylindrical or torpedo-shaped bodies with a single eye and a pair of long antenna at the front, five pairs of legs along the middle and a paddle-like tail at the end.
How long does it take for a pond to hatch?
Some eggs are resistant and do not hatch until the pond fills. Some emerge within 24 hours of the pond filling; others may take days or weeks to emerge.
What is a cladoceran?
Cladocerans, commonly called water fleas, have been favorite objects of observation by both amateur and professional biologists since the invention of the microscope.
Where do zooplankton live?
Zooplankton are small animals that live in the water column of almost all water bodies, including oceans, lakes and ponds , although they mostly cannot survive in rivers and streams.
What is zooplankton?
Zooplankton are critical parts of freshwater ecosystems, but often get forgotten. Scientist Mike Paterson explains what zooplankton are, and why they matter. By Michael Paterson on June 26, 2019. Whenever I speak to the public as a researcher on water quality, I often hear four big questions:
What species of zooplankton are in the Canadian lakes?
In recent years, many species of zooplankton have been accidentally introduced to Canadian lakes and rivers from Europe and elsewhere, including the spiny water flea ( Bythotrephes) and the larval stages of zebra mussels. Occasionally, some species of zooplankton, such as Mysis, have been deliberately introduced to lakes to enhance fish production.
Is biomanipulation effective for algae?
This research, in conjunction with other studies, suggested that biomanipulation can effectively reduce algae in the short term, but may be less effective as a long-term solution for eutrophication. Ultimately, biomanipulation is most effective when combined with nutrient reduction strategies.
What do zooplankton eat?
Most zooplankton eat phytoplankton, and most are, in turn, eaten by larger animals (or by each other).
How big is plankton?
Plankton are usually microscopic, often less than one inch in length, but they also include larger species like some crustaceans and jellyfish. Scientists classify plankton in several ways, including by size, type, and how long they spend drifting.
What are the two groups of phytoplankton?
But the most basic categories divide plankton into two groups: phytoplankton (plants) and zooplankton (animals). A microscopy image of Protoperidinium quinquecorne enhanced with a fluorescent dye. The chlorophyll pigment is shown in red. This is one example of thousands of types of phytoplankton.
What is a plankton?
Plankton are marine drifters — organisms carried along by tides and currents. Phytoplankton blooms in the Barents Sea, shown in natural color from NASA's Aqua satellite on July 10, 2014.
What do krill eat?
Krill may be the most well-known type of zooplankton; they are a major component of the diet of humpback, right, and blue whales. During the daylight hours, zooplankton generally drift in deeper waters to avoid predators. But at night, these microscopic creatures venture up to the surface to feed on phytoplankton.
Why are plankton important to the ocean ecosystem?
Plankton are incredibly important to the ocean ecosystem, and very sensitive to changes in their environment , including in the temperature, salinity, pH level, and nutrient concentration of the water. When there are too many of certain nutrients in the water, for instance, harmful algal blooms like red tides are the result.
Why is plankton considered a living thing?
An organism is considered plankton if it is carried by tides and currents, and cannot swim well enough to move against these forces. Some plankton drift this way for their entire life cycle. Others are only classified as plankton when they are young, but they eventually grow large enough to swim against the currents.
Zooplankton Definition
What Do Zooplankton Eat?
- Zooplankton consume a variety of bacterioplankton, phytoplankton, and even other zooplankton species. Since such organisms reside at the surface of bodies of water, zooplankton are also typically found in the upper waters.
Zooplankton Examples
- Krill
Krill (shown below) are a type of crustacean found populating oceans throughout the world. Krill consume phytoplankton and other zooplankton species. Krill are consumed by larger marine animals, thus making them a significant contributor to the lower food chain in marine environme… - Jellyfish
Jellyfish (shown below) are a type of cnidarian as described above, and are found residing throughout marine environments; some reside near the surface, while some species can be found in deeper waters. Jellyfish are most commonly found near coastal regions throughout the world.
Quiz
- 1. Which of the following is NOT an example of a type of zooplankton? A. Krill B. Jellyfish C. Leech D. Squid E.None of the above 2. Which of the following is NOT food for zooplankton? A. Other zooplankton species. B. Phytoplankton C. Aquatic mammals D.None of the above. Zooplankton are photosynthesizing species and do not require additional food.
Summary
Zooplankton are heterotrophic (sometimes detritivorous) plankton (cf. phytoplankton). Plankton are organisms drifting in oceans, seas, and bodies of fresh water. The word zooplankton is derived from the Greek zoon (ζῴον), meaning "animal", and planktos (πλαγκτός), meaning "wanderer" or "drifter". Individual zooplankton are usually microscopic, but some (such as jellyfish) ar…
Taxonomic groups
Protozoans are protists that feed on organic matter such as other microorganisms or organic tissues and debris. Historically, the protozoa were regarded as "one-celled animals", because they often possess animal-like behaviours, such as motility and predation, and lack a cell wall, as found in plants and many algae. Although the traditional practice of grouping protozoa with an…
Overview
Zooplankton are the animal component of the planktonic community ("zoo" comes from the Greek word. for animal). They are heterotrophic (other-feeding), meaning they cannot produce their own food and must consume instead other plants or animals as food. In particular, this means they eat phytoplankton.
Zooplankton are generally larger than phytoplankton, mostly still microscopic but some can be s…
Size classification
Body size has been defined as a "master trait" for plankton as it is a morphological characteristic shared by organisms across taxonomy that characterises the functions performed by organisms in ecosystems. It has a paramount effect on growth, reproduction, feeding strategies and mortality. One of the oldest manifestations of the biogeography of traits was proposed over 170 years ago, namely Bergmann’s rule, in which field observations showed that larger species tend t…
Role in food webs
Grazing by single-celled zooplankton accounts for the majority of organic carbon loss from marine primary production. However, zooplankton grazing remains one of the key unknowns in global predictive models of carbon flux, the marine food web structure and ecosystem characteristics, because empirical grazing measurements are sparse, resulting in poor parameterisation of grazing functi…
Role in biogeochemistry
In addition to linking primary producers to higher trophic levels in marine food webs, zooplankton also play an important role as “recyclers” of carbon and other nutrients that significantly impact marine biogeochemical cycles, including the biological pump. This is particularly important in the oligotrophic waters of the open ocean. Through sloppy feeding, excretion, egestion, and leaching of fecal …
See also
• Bacterioplankton
• Biological pump
• Census of Marine Zooplankton
• Diel vertical migration
• Gelatinous zooplankton
External links
• SAHFOS Sir Alister Hardy Foundation for Ocean Science
• Ocean Drifters Short film narrated by David Attenborough about the varied roles of plankton
• Sea Drifters BBC Audio slideshow
• Plankton Chronicles Short documentary films & photos