Crayfish Essay

The water in the hot bag was approximately 65° Celsius. We allowed the shrimp to move about for 30 minutes because we had the time. Every 10 minutes we replaced the hot water in the bag with fresh hot water because it was slowly cooling down. After the 30 minutes were up we closed the clamps and removed the hot and cold bags from the tubing and counted the number of shrimp in each section and recorded our results. We did not count any dead shrimp because that condition would obviously not be a condition they could survive in. In this part of the lab we measured the temperature of water from each section and recorded that number also. We did this by simply pouring the water from each section into 4 different test tubes and placing a thermometer in each.

2006). The rusty crayfish is a generalist omnivore, and eats a variety of organisms from invertebrates to algae to small fish and even predates piscivore eggs (Kreps et al. 2016). This feeding behavior is consistent with almost every other crayfish species (Renai and Gherardi 2004). However, compared to native crayfish, the rusty crayfish grows faster, has a larger body and pincers, and is less susceptible to predation even as a juvenile (Perry et al. 2001). As a result, the rusty crayfish is a better predator than native crayfish and preys on organisms at a higher rate than native

Signal crayfish (Pacifastacus leniasculus) is an invasive species in UK and European freshwaters which originate from North America and was introduced in Europe in the 1960s. Due its large size body and aggressive nature has threatened the native species, white-clawed crayfish (Austropotamobius pallipes). Aggressive behaviour is bolder in signal crayfish species, which is directed also against conspecifics not only against other species (Pintor, Sih and Bauer 2008). Signal crayfish is widespread across the British Islands; predominantly inhabiting south-west part where for the first time was introduced. The motility of signal crayfish depends of temperature, and is higher during the summer period (Bubb, Thom and Lucas, 2004). Signal crayfish

The body of a crawfish, which is a decapod crustacean, comprises of as many as nineteen distinctive body parts that are collectively combined into two primary body parts. These two are the cephalothorax followed by the abdomen. Furthermore, each of the body segments has two appendages. In general an average

The purpose of this experiment is to determine the effect of population density on Artemia Salina. Artemia Salina are brine shrimp that live in waters with high salinity levels, similar to the novelty pet “Sea Monkeys”. If the number of artemia in an enclosure is higher, then the lifespan of the Artemia Salina will be shorter. Three beakers were filled with varying levels of population density and monitored over 6 days. The trend in the data showed that higher population density contributes positively to the lifespan of Artemia Salina.

The fishes varied in weight ranging from an average of about 7.2 to 10.1 grams, and out of eight trials, one consisted of two fish undergoing control and experimental conditions to measure changes in oxygen concentrations. The goldfish in darkness had a higher oxygen consumption rate of 347 mgO2/(L*hr) than goldfish in ambient lighting, a rate of 259 mgO2/(L*hr). The standard deviations for the control and experimental groups undergoing darkness was 81 mgO2/(L*hr) and 105 mgO2/(L*hr) respectively. An unpaired t-test was recorded, and the p-value was 0.081. Discussion:

It was also shown that the crayfish had a higher metabolic rate than the mouse. My hypothesis was completely incorrect in stating that the crayfish would have a lower metabolic rate than the mouse. The slope of the crayfish’s linear regression was negative, while I had hypothesized that it would be positive. I was correct in guessing that the endotherm’s metabolic rates would remain steady, which they did with only a slight bit of fluctuation. I believe that there was a significant amount of error in this experiment because many documented facts pertaining to this subject state that the metabolic rate of the crayfish should climb when exposed to higher external temperatures. ‘a warm body temperature contributes to higher levels of metabolic activity’ (Campbells,p899). ‘when ectotherms increase their body temperature using the external environment, their metabolism increases as well’ (Grolier,1996). Both these pieces of literature state that the metabolism rises as the body temperature rises. My results state that as temperature rises, metabolism drops. Possible reasons for this could be the size of the crayfish used. If each crayfish was a different size, then the larger crayfish would consume more oxygen from the same sized flask than a smaller crayfish might. Therefore, the initial metabolic results could have been from larger specimens

Procambarus Clarkii, also known as the Red swamp crayfish/crawfish, or Louisiana crayfish/crawfish, is a decapod crustacean having two distinct body divisions. There is the anterior cephalothorax with paired appendages including antennae, mouthparts, and walking legs and the major body organs and the posterior abdomen containing the major abductor muscles for rapid backward escape from real or perceived threats, and paired appendages associated with sperm transfer in males and incubation of eggs and developing embryos in females and the tail ‘fan’ in both sexes.

Description of Experiment:In this experiment to test the effect of colder temperatures on goldfish respiration rate.We started with a beaker

that the most commonly identified environmental variable inducing sex change is temperature. Further, he had also

There are many similarities and differences in the gas exchange systems of mammals and bony fish, due to the way they have adapted to fit their particular environments.

An investigation into the effects of varying seawater concentrations on two marine invertebrates’ osmoregulatory abilities; Carcinus maenas and Arenicola marina.

The Aquatic crustacean Artemia Franciscana is a significant organism for models in scientific studies on ecology and phycology and has increasingly been exploited for use in aquaculture as a commercial resource (Irwin, S., Wall, V. & Davenport, J. 2007). Artemia Franciscana commonly referred to as brine shrimp are widely distributed in inland salt water bodied niches of lakes and estuarine areas around the world where their main nutritional sources are obtained (Irwin, S., Wall, V. & Davenport, J. 2007). In these ecological niches they experience large fluctuations in their physicochemical environments, predominantly temperature, nutrition, salinity and oxygen tension (Irwin, S., Wall, V. & Davenport, J. 2007). Artemia Franciscana is considered a phagotrophic filter feeder (Evjemo, J.O. & Olsen, Y. 1999) which uses its larval antennae to start ingesting food (Evjemo, J.O. & Olsen, Y. 1999). The optimal temperature for growth in Artemia Franciscana ranges between 25 and 30oC (Evjemo, J.O. & Olsen, Y. 1999). Among these various factors affecting aquatic species, the level of nutrition quality is paramount to metabolic rates and fecundity. Every animal has different nutritional targets that are needed for optimal performance function (McGrill, 2010). Nutrition quality is broken into two main components of energy content, micro and macro nutrients

In addition, some marine populations are dwindling due to the fact that they cannot adjust being stripped away from nutrients they have been accustomed to receiving and the slight change in their surrounding environment in which they are supposed to survive and thrive in. For example, the urchin Paracentrotus lividus and Planktonic larvae are one of the many populations being affected by the alteration. Overall, many populations have a specific range of body temperatures in which they can survive in and if the exterior temperature is affecting this, then a negative consequence can occur. Furthermore, interactions between environmental stressors and temperature have the potential to narrow the types of species that will continue to live, decreasing numbers exponentially. (Garcia) Therefore, temperature displays how it is the most important environmental factor controlling the behavior, distribution,, morphology, and physiology of marine invertebrates. For the Planktonic larvae, the warming can help fertilization but a negative consequence is their time span for their lives may be reduced, which can have a bigger result than expected. With them living for less amounts of time, the predators have less of a chance to capture them but with them living for a shorter period of time, the distance they typically travel in their life may be reduced, as well, altering the connectivity between populations for the better or for the worse. Other marine life being affected as well, besides

This paper will review the current literature surrounding environmental changes that are impacting jellyfish and how these organisms are reacting/adapting to these impacts. This includes a changing range of habitats, issues related to ocean acidification, and physiological changes to the organism. Most of the information in this paper will draw from published scientific