Relationship Between Starfish And Crabs

Mutualism is when two organisms have a relationship in which both of them benefit.An example of mutualism is algae and the spider crab.Since spider crabs spend most of their time in shallow water they can be seen by predators.Algae will make the spider crabs back their home.Now with the algae on their back, the spider crab is able to disguise itself from predators.If the spider crab did not have the algae it would be eaten by predators,if the algae didn't have the spider crab it would not have a home.

Although it supports a number of different organisms, Nudgee Beach lacks many of the fundamentals that make up a healthy and successful ecosystem. The first indicator of this is from the lack of birds present in the area. Although it has been noted for terrestrial bird species – such as kingfishers, pelicans, ibis, egrets, jabiru, stilts and heron – and wading bird species – such as golden plovers, curlews, tattlers and godwits – to have been spotted at Nudgee Beach and surrounding areas in the past; after a day’s worth of extensive observation and research, it was found that the birds observed were limited to magpie, ibis, great knot and eastern curlew species. To intensify this factor, at the time by which this lack of species was recorded, Nudgee Beach was expected to have started seeing tens of thousands of birds arrive for the migratory season [21]. This blatant lack of bird species diversity and quantity may have been due to the lack of small organisms within the ecosystem. The restricted number of small organisms at Nudgee Beach is detrimental to the entire ecosystem as these organisms make up the bottom levels of the food web and provide higher-level organisms with adequate amounts of food to consume. The smaller organisms expected to be observed – including; crustacean, shell, mollusc, lizard, frog, fish, worm, arachnid and insect species – was limited to the infrequent observation of crustacean, shell,

In this research paper I will talk about how a large decrease in the algae population in the Chesapeake Bay will cause problems for not just fish and other species but the people who fish and make a living off of it. A large decrease in algae population will have a domino effect on the food chain. Having a major decrease in algae will hurt how others species live and protect themselves.

Primary producers produce their own nutrients, and make their own food through photosynthesis. Those organisms are plankton and sea weeds. The second on trophic levels are the secondary consumers such as smaller fish and sea urchins. Third on the trophic levels are decomposers. Decomposers are lobsters and sea turtles. Tertiary consumers are the top of the food chain, they are sharks and bigger fish. Predation is major in a coral reef because there is so much food supply. Mimicry is used to keep the predators away but wearing bright

The area of research that I have selected is the effects of overfishing in the Sea Otter ecosystem off the coast of California. The effects caused by the fishing pressure on the ecosystem will have different outcomes, depending on the strength and the types of relationships of the organisms present. (4) Red Abalone populations have declined drastically, to the point of the abalone fishery collapse. Several factors have led up to the collapse including Withering Syndrome, where the organism loses the ability to attach itself to rocks, making it more susceptible to predation, or the organism can eventually wither and starve to death. Sea Urchins and Red Abalone are a part of the same ecosystem, and are competitors of each other.(5) Both organisms graze on macroalgae and are a primary food source for Sea Otters. Sea Otters occurred from the North Pacific Rim down to Baja California, Mexico, but now only occur in small isolated patches (9) It is understood that Sea Otter presence can characterize community structure, where they can control and determine the size of Sea Urchin and Red Abalone populations. In the absence of Sea Otters, “Urchin Barrens” are created from the overgrazing of macroalgae by Sea Urchin. In these areas the ecosystem have changed dramatically, due to the overfishing, or in this case the over hunting, of Sea Otters causing a trophic cascade.(7)In some areas, Sea Otters have been reintroduced, in other areas they were never removed, and in others they

You scratch Giant Crab 1 in the left first leg from behind, fracturing the chitin and bruising the fat!

Know the adaptations of organisms found in the tidal pool ecosystem – to do this, match up the following

The food web of Numbinbah Valley ( see appendix 5) and Hastings Point ( see appendix 6) shows that the relationship between phytoplankton and detritus, microorganisms and other decaying matter (producers) have a mutualistic relationship, which is a symbiotic relationship in which both individuals benefit from the association. The food webs of Numbinbah and Hastings Point visualized a common mutualistic relationship that detritus and microorganisms are eaten mainly from primary consumers such as mollusucs (The primary consumers pink barnacle, common limpet, sea stars, chiton and blue periwinkle) and insects (flies, moths and ants). The connection between the mosquito and the detritus in the Numbinbah Food Web, can be also classified as parasitism which is where one organism benefits at the expense of another organism. Mosquitos feed on the blood of the organism and may cause diseases such as malaria towards the host. Another connection between the two webs is birds are the tertiary consumer in both environments where the tertiary consumers feed on the secondary consumer. The webs of Hastings Point and Numbinbah Valley describe the consistent relationships of producers, primary consumers, secondary consumers, tertiary consumers and decomposers. The Hastings Point and Numbinbah Valley have a lot in common as both show a common

Sea otters (Enhydra lutris) are marine mammals capable of spending their entire lives in water. Being carnivorous in nature, they feed on sea urchins, crabs, fishes, mussels and clams. They are referred to as keystone species due to their profound impact on marine ecology. The interaction between sea otters, sea urchins and kelp forests has been studied as a model for the impact of predator-prey interactions on community ecology. Sea otters are keystone predators, whose presence has a far-reaching influence on the marine food web by affecting the populations of sea urchins, which indirectly affects the populations of kelp

Our end results only supported to some extent our hypothesis that increasing numbers of brine shrimp would directly cause decreases in algae concentration. Our hypothesis, if applied to only the jars of 3 and 6 brine shrimp, would be highly supported, due to the significant difference in algae concentrations. Evidently, the more shrimp that were present in the ecosystem, the less algae that were available at the end. In an ecosystem with more consumers, the consumers demand a higher amount of nutrients from the environment, or more specifically, the producers. And as the consumers develop and grow, those demands also grow. And thus, when we increased the amount of brine shrimp, more algae were consumed per unit time. Though the rate of consumption from the brine shrimp did not exceed the rate of growth of the algae in any jar, the

Although the first three stages of an invasion are important to understanding the invader, the impact stage of invasion is more important because it includes all the effects an invader has on the invaded ecosystem. For the rusty crayfish, Orconectes rusticus, the impacts it has on an invaded area are a result of its natural behavior (McCarthy et al. 2006). Although this behavior is similar to native crayfish, the rusty crayfish is faster and more resilient than any other native crayfish (Kuhlmann 2008). As a result, the rusty crayfish not only outcompete other native crayfish, but also extensively preys on species that are used to the more passive and slower native crayfish (McCarthy et al. 2006). The impacts of the rusty crayfish on new environments include the direct and indirect effects of decreases in local populations, and hybridization with native crayfish species due to its ability to outcompete native crayfish.

The Atlantic cod fishery collapse left terrible ecological consequences. As mentioned above, the fishing technology was a major destruction to the ecological system by using deployment and draggers. The huge nets that were dropped and dragged along the bottom of the ocean destroyed the underlying eco-system in the process. The effect of selective fishing on spawning grounds – that is, selectively over-exploiting one species in an ecosystem – had disastrous effect on the feeding relationships in that ecosystem. This contributes to the overall reduction of spawning stock biomass of the targeted species, but also an increase in the number of invertebrate and vertebrate predators such as crustacean and fish which will prey on cod eggs, larvae, and younger fish. It is a little wonder that a species like cod, would eventually run into difficulties struggling to survive when its habitat is being continuously destroyed and the balance of their food chain had been wiped out.

Some starfish may perform this function by preying on sea urchins, mussels, and other shellfish that have no other natural predators. If the sea star is removed from the ecosystem, the mussel population explodes uncontrollably, driving out most other species, while the urchin population annihilates coral reefs.

The coral reef surveyors were instructed to find the best sites that they believed had the most living coral and were thought to be least affected by human activities. This would allow Hodgson to determine if human activities were having an appreciable effect on the supposed pristine coral reefs, which were distant from urban centers. The invertebrate survey was undertaken at two depth intervals of 3m and 10m. Four 0.5 m wide by 20 m long belts were placed on the coral reef. Over a period of 3-5 minutes the observers counted the number of invertebrates found on the belts. The coral survey was performed, by placing four 20 m long belts on the coral substrate. At 0.5 m intervals the substrate on which the belts were lying was examined and recorded.

The intertidal rocky shore of Caloundra Beach is inhabited by diverse range of biodiversity of animals and plants, many of which have developed high levels of adaptations throughout their existence. The very boundary of marine and terrestrial ecosystem, this environment is subjected to extremes of the physical environment such as temperature, desiccation, wave turbulence as well the ecological interactions that commonly occur in biotic communities (e.g. competition, predation). However Rocky intertidal shores are easily accessible by humans and provide an enjoyable opportunity for passive recreation and for science and environmental education as well.