Search results
Results from the WOW.Com Content Network
In zoology, deep-sea gigantism or abyssal gigantism is the tendency for species of deep-sea dwelling animals to be larger than their shallower-water relatives across a large taxonomic range. Proposed explanations for this type of gigantism include necessary adaptation to colder temperature, food scarcity, reduced predation pressure and ...
Zooplankton and salps play a large role in the active transport of fecal pellets. 15–50% of zooplankton biomass is estimated to migrate, accounting for the transport of 5–45% of particulate organic nitrogen to depth. [40] Salps are large gelatinous plankton that can vertically migrate 800 meters and eat large amounts of food at the surface.
The stable ocean hypothesis (SOH) is one of several hypotheses within larval fish ecology that attempt to explain recruitment variability (Figure 1; [1] Table 1). The SOH is the notion that favorable and somewhat stable physical and biological ocean conditions, such as the flow of currents and food availability, are important to the survival of young fish larvae and their future recruitment.
However, this zone is difficult for fish to live in since food is scarce; resulting in species evolving slow metabolic rates in order to conserve energy. [48] Occasionally, large sources of organic matter from decaying organisms, such as whale falls , create a brief burst of activity by attracting organisms from different bathypelagic communities.
Their maximum recorded depth is 1,888 meters (6,194 feet), and the maximum duration is 85 minutes. [2] Air-breathing marine vertebrates that dive to feed must deal with the effects of pressure at depth, hypoxia during apnea, and the need to find and capture their food. Adaptations to diving can be associated with these three requirements.
A food web is network of food chains, and as such can be represented graphically and analysed using techniques from network theory. [1] [2] Classic food web for grey seals in the Baltic Sea containing several typical marine food chains [3] The fourth trophic level consists of predatory fish, marine mammals and seabirds that consume forage fish.
The temperature variations are large; from over 20 °C (68 °F) at the upper layers to around 4 °C (39 °F) at the boundary with the bathyal zone. [5] The variation in salinity is smaller, typically between 34.5 and 35 psu. [5] The density ranges from 1023 to 1027 g/L of seawater. [5]
Removal of piscivorous fish can change lake water from clear to green by allowing phytoplankton to flourish. [24] In the Eel River, in Northern California, fish (steelhead and roach) consume fish larvae and predatory insects. These smaller predators prey on midge larvae, which feed on algae. Removal of the larger fish increases the abundance of ...