Impect of climatic change on aquatic life

Trophic cascading interrelationship of aquatic communities

Monitoring and Conservation of tropical lake using cascading interrelationship analysis of aquatic communities with reference to climate changes.

Dr. Asma Ali

[Ecologist]

INTRODUCTION:

Trophic relationships are a vital component of community structure in aquatic bodies, particularly with respect to predation, competition and resource spiraling of the major components such as plankton, macroinvertebrate and fishes. Dietary habits can potentially influence every aspect of the life of the aquatic fauna, such as life cycle, choice of habitat and behavior.

Consequently the trophic ecology of aquatic fauna has received much attention from ecologists, however most of the work has been done in temperate regions of the Northern Hemisphere (Hairstone and Hairstone 1993, Merrit and Cummins 1996, Duffy 2005) and to a lesser extent, the Southern Hemisphere (Chessman 1986, Yule 1996, Kaunzinger and Morin 1998, Winemiller and Layman 2005). Data on the dietary habits of aquatic invertebrates and vertebrates are not common, particularly for organisms of tropical water bodies of central India.

Aquatic ecosystem functioning depends on multiple interactions between physical, chemical and biological determinants. Indeed, ecosystem process (productivity and nutrient recycling) result directly from the diversity of functional traits in the biotic communities, which is in turn determined by the species composition and diversity (Kelly and Haves 2005, Zanden and Fetzer 2007, Adandedjan et al. 2010). This species diversity results from both biotic interaction and environmental pressures. As a result, changes in biodiversity in response to environmental selection pressures tend to have a direct impact on ecosystem process. 

Thus these intricate relationships between aquatic biodiversity and ecosystem functioning has been the focus of numerous researches for several years, particularly in the event of drastically changing global climate scenario, however large tropical man made water body, such as the Upper Lake in Bhopal, has not at all been subjected to a food web interrelationship analysis. Thus there is no information available on the comparative assessment of climate change scenarios based on aquatic food web modeling, resulting in a rapid eutrophication of this largest man made lake.                         

In an aquatic ecosystem, each species either invertebrate or vertebrate has the potential to perform an essential role in the persistence of the aquatic food web and the ecosystem and that species may remain as the sole representative of a particular functional group. At some level where each species is unique, overlapping in resource use among species in not unusual, especially in freshwater food webs.

Many benthic invertebrates are predators that control numbers, locations and sizes of their prey, benthic invertebrates supply food for both aquatic and terrestrial vertebrate consumers e.g. fishes, turtles and birds, finally benthic organism accelerate nutrient transfer to overlaying open waters of lakes as well as to adjacent riparian zones of streams (Abell et al., 2008, Heino et al. 2009, Matthews and Wickel 2009).

The extent of understanding the effect of aquatic fauna and flora in a freshwater ecosystem food web process varies with the type of fresh water system. Food chain length is a measure of the number of energy transfer or trophic link between primary producers and top predators in an ecosystem also plays an important role in regulating biogeochemical fluxes, fisheries productivity and contaminant bioaccumulation in top predators of any water body.

Climate change is one of the most crucial and influential ecological problems of our age, therefore a large number of investigations is required to deal with this problem which is increasing permanently. Climatic changes and variability can influence aquatic ecosystem in a very sensitive way, so the research of the possible effects of climate change on aquatic ecosystem means an indispensable task.

Global warming and climate change which has caused the ecological systems, biodiversity and human life to control the biggest problem of history have started to show their impacts on all living beings in the aquatic ecosystem from plankton to mammals. Global surface temperature has increased on an average of 0.74 ± 0.18ºC between the start and the end of the 20th century (Abell et al. 2008, Matthews and Wickel 2009, Heino et al. 2009).

Since we do not have the chance to reverse global warming and climate change phenomena, the only thing that needs to be done is to minimize the foreseen harms in the future. To this end, mankind needs to understand the global warming problem and cooperate on an international level using aquatic model studies of invertebrate and vertebrate species preferably in large tropical water bodies, which are in brink of eutrophication and extinction.

Upper Lake of Bhopal the largest man made lake built by Raja Bhoj in 1100 is such an example. The present work will be a very important step towards its conservation.

Previous studies of Upper Lake have often dealt with the physico-chemical parameters for taxonomy of flora and fauna of the lake (Durrani 1993, Tiwari 1999), which are clearly important components of food webs, but how their functional relationships respond to changes in species composition are not known at all. Crores of rupees have been spent by Lake Authority Bhopal and other agencies on only physicochemical and limnological studies of the lake with no data available on cascading trophic interactions of invertebrate communities; except for the preliminary work of Parveen et al. (2009), Parveen and Ali (2010), which have shown interesting findings. 

In the present research work, we will be highlight examples of how some species have a disproportionately large impact on food-web dynamics, how particular species provide essential ecosystem services and how changing climate impacts aquatic biodiversity. These ecosystem functions include sediment mixing; nutrient cycling, cascade prey predator relationship and energy flow through food webs. The present investigation will prepare a working model of lake monitoring and conservation using aquatic food web cascading interrelationships in changing climate factors likes temperature, humidity, rainfall and nutrients.

AIMS AND OBJECTIVES :

1. To investigate the trophic importance of plankton (phytoplankton and zooplankton) in relation to species richness and pelagic primary productivity of the Lake with regard to rainfall, temperature humidity and nutrient.
2. To determine the number of trophic  in an aquatic ecosystem and to focus the role of benthic invertebrate species in freshwater ecosystem.
3. To assess the role of insect fauna in water quality assessment programme and their importance in aquatic food web in relation to limnological factors.
4. To group the various fish species according to their feeding preferences, for assessing functioning of cascade trophic prey-predator relationship in the Lake.
5. To investigate the role of macrophytes with regard to their trophic status for management and conservation of the Lake.
6. Comparative assessment of the alternative climate change scenarios using statistical methods.

BRIEF REVIEW OF THE WORK DONE IN THE FIELD:

 

Food chain length is a measure of the number of energy transfer or trophic links between primary producers and top predators in an ecosystem, and the importance of food chain for ecosystems and their functioning have been widely documented. For example, the number of trophic levels in a central consideration to the study of the food chain dynamics (Fretwell 1987) and the structuring of the ecosystem via trophic cascades (Kelly and haves 2005, Zanden and Fetzer 2007) as well as mediating the relationship between species diversity and function (Worn 2002, Schmitz 2003, Duffy 2005).

 

Food chain also plays a role in regulating biochemical fluxes, fisheries productivity (Pauly and Christensen 1995) and contaminant bioaccumulation in top predators (Kidd 1995, Winmiller and Layman 2005).

The earliest consideration of food chain, Elton (1927) speculated that available energy ultimately limits the number of trophic levels in ecosystems. A clear prediction is that more productive should have longer food chains. This “productivity hypothesis” has found support in some studies (Kaunzinger and Morin 1998, Thompson and Townsend 2005, Kundzewicz et al., 2008), but not others (Briand and Cohen 1987). 

 

Since then, variants of the productivity hypothesis have been forwarded, most notably the productive space hypothesis, which argues that total ecosystem production should best reflect the capacity of an ecosystem to support additional trophic levels and the hypothesis that food chain length should increase with increasing ecosystem size (Post et al. 2000).

In the case of aquatic ecosystems the astonishing species richness in phytoplankton communities has stimulated many studies of the importance of competition for light and /or nutrients, or of the intermediate disturbance hypothesis have been reported by several workers such as Elliott et al. (2002) and Schippers et al., (2001). 

Similarly in case of zooplankton many views have been stressed by several investigators such as Leveque (1997) and Matondo and Msibi (2006), who showed the relationship between zooplankton and physico-chemical features of a water body, while Ward (1998) stated that there is no obvious relationship between zooplankton and dissolved nutrients. In freshwater sediments, benthic invertebrates are diverse and abundant and the integrity of the freshwater supply depends on how various benthic species make their living and contribute to complex food web.

Furthermore, there are many papers that deal more specifically with the mechanisms involved in the relationships between biodiversity of water bodies and ecosystem functioning. Notably have Yule (1996), Loreau (1998) and Conway (2005). Using a freshwater microbial community Fukami and Morin (2003) found that food web relationships in the different assemblage of species took various forms (U-shaped, hump-shaped) after 30 generations.

Concerning aquatic ecosystems more particularly Dobson et al. (2000) found in their study based on a survey of 33 lakes that for both phytoplankton and fish, the richness-productivity relationship was highly dependent on the area of the lake.

Climate change has and will continue to affect freshwater ecosystems in a variety of ways (Fukamy and Marin 2003, Heino et al.,2009). When flow regimes shift, quantitative and qualitative changes to aquatic habitat result, indirectly influencing ecosystem productivity and biodiversity. Freshwater systems are expected to experience an increase in the frequency and intensity of extreme events, such as droughts and floods ;freshwater species adapted to different, historic flow regimes might be unable to complete their life histories under these conditions. 

Climate change-induced air temperature shifts are already altering water temperature and attendant biogeochemical processes, and changes in lake volume and thermal structure are expected (Lake et al. 2000; Mohseni et al. 2003). Coastal wetlands and the lower reaches of most rivers in many regions have been affected by sea-level rise for over a century (Bates et al. 2008).

However there are very few studies on trophic relationships of water bodies and ecosystem functioning, some of these studies which have contributed to the significant advances of our knowledge on this subject in the last ten years and have provided a good overview of the challenges likely to face us in the future. 

With this goal in mind, new experiments based on trophic relationships and food web must be performed at aquatic ecosystem of tropical water bodies, which have variant cycles of trophic interactions due to large number of environmental factors. Thus in the view of above lacunae, the present study has been taken, where a detailed study of tropical lake using cascading interrelationship analysis of aquatic communities with reference to climate change.

DESCRIPTION OF STUDY AREA :

The Upper Lake is located in Bhopal city, the capital of Madhya Pradesh, the largest state of India. Constructing on earthen dam across the river Kolans in the 11th century created this lake. The Upper Lake has water spread area of 30.72 sq.km at FTL. The storage capacity is 101.6 million cu.m, the maximum and mean depth being 11.7 and 6 m. respectively. 

The Upper Lake is under a massive conservation, restoration and management project funded by overseas Economic Cooperative Fund (OECF) Japan to protect it from environmental degradation not only due to its natural aesthetic value and rich biodiversity, but also since it is the main source of potable water. Selection of the sampling sites of the Upper Lake chiefly was done on the basis of weeds and consequent biomass sampling. Sampling will be done at four sampling sites of Upper Lake viz. Bhadbhada, Van-vihar (National Park), Pump-house and Bairagarh

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Dobson S.I. ,S.E. Arnott and K. L. Kottingham (2000) The relationship of lake communities between primary productivity and species richness, Ecology 81, 2662-2679.

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how does Notonecta maculata (Odonatan) effects Dipteran communities?

Lake ecology
Dr.Asma Ali [Ecologist]

November 2019

Effect of predatory backswimmer on Dipteran communities

Effect of Predatory backswimmer N. maculata on community structure of Dipterans

Abstract :

Impact of predator N. maculata on distribution and abundance of Dipteran species Culiseta longiareolata, Tendipes tendipes and Tendipes kifferulus were investigated in an Urban Lake, Upper Lake Bhopal, India.  The impact of invertebrate predation as observed in the present study (where the abundance of Notonecta maculata decreases, population of Dipteran species), has been documented for the first time in tropical waterbody, particularly in fresh water Lake. This work provides strong evidence that N. maculata is an important organizer of community structure and strongly reduces or even eliminates larger pelagic or neustonic species, but does not affect densities of small or benthic species.

Introduction :

The population abundance of aquatic insects are usually attributed on the basis of physico-chemical parameters of water bodies by many workers (Crosswell 1949, Mitchell 1959, Smith 1988, Singh 1995, Ravera 2001, Solimini et al. 2003, Arimoro et al. 2007). A second potential source of population abundance of aquatic insects has received less attention in density - dependence interactions between insects and their food competitors or natural enemies (Hutchins 1966, Andres & Cordero 1998, Yule 1996 and Gergs and Ratte ,2009). These early studies led to an explosion of experiment which documented the effect of aquatic insect Notonecta maculata on population abundance of dipteran community in tropical lake of India.

The importance of invertebrate predators in structuring communities has received less attention, but the growing number of prey-predators relationships show that they play an important role in aquatic ecosystem (Leucke & Litt 1987, Lounibos et al. 1987, Blaustein 1990, Blaustein & Ward 1995, Matveev 1995 and Andres & Cordero 1998). Notonecta maculata belongs to family Notonectidae is most common predator of aquatic system, have been shown to have a large impact on dipteran populations as well as other macrobenthic fauna (Scott & Murdoch 1983, Chesson 1984, Murdoch et al. 1984).

          

The potential role of predators in causing cascading frequently over the last decade (Kerfoot 1987; Bronmark et al. 1992, power 1992, Carpenter & Kitcheil 1993) by directly reducing primary consumer populations, predators such as N. maculata may indirectly cause an increase in algal Proliferation. There are no long term studies of the impact of N. Maculata predation in natural populations of dipterans in tropical lake. The objective of this study was to determine whether N. maculata reduce survival and population abundance of dipterans in waterbody.

N. maculata Fabricius (Hemiptera : Notonectidae) is a pelagic predator, feed on dipterans, that have been the subject of many laboratory studies to assess predatory habits and prey behaviour (Sih 1980, Giller & Mc Neill 1981, Scott and Murdoch 1983, Streams 1994, Sherratt and Mac Dougall 1995) outside the laboratory there is a less number of predatory behaviour of Notonectidae, in temperate lake (Ellis & Borden 1970, Hazelrigg 1974, Chesson 1989, Blaustein et al. 1995) although not a single prey- predator relationship in case of N. maculata has been recorded so far in tropical lake of India.

Description of the study area -

The Upper lake is located in Bhopal city, the capital of Madhya Pradesh, the largest state of India. This lake was created by constructing on earthen dam across the river Kolans in the 11th century. The Upper Lake has water spread area of 30.72 sq.km at FTL. The storage capacity is 101.6 million Cu.m, the maximum and mean depth being 11.7 and 6 m. respectively.

Outflow from the Upper Lake which receives water, mainly through the Kolans river drains into Kaliasot river and finds its way to Yamuna river though the Betwa river. The Kolans river feeding the Upper Lake, being a seasonal river flows for few days immediately after heavy rain. A waste weir at Bhadbhada controls overflow and thereby facilitate flood control.

Upper Lake is divided into perennial water, covered, marshy and submerged cum transitional zones. Due to the shallow nature of the last zone the lake becomes exposed from post monsoon period to summer season. Therefore the lake supports mainly 3 types of vegetation consisting of more than 100 terrestrial or marshy plant species and 34 aquatic species. The aquatic species have been categorised as floating forms (10 in number) submerged forms and emergent forms.

The lake is rich in biodiversity, principle components being aquatic vegetation includes 106 species of macrophytes, 208 phytoplankton species, 105 zooplankton species and 98 aquatic or shoreline insects.

The Upper Lake is under a massive conservation, restoration and management project funded by overseas Economic Cooperative Fund (OECF) Japan to protect it from environmental degradation not only due to its natural aesthetic value and rich biodiversity, but also since it is the main source of potable water. Selection of the sampling sites of the Upper Lake chiefly was done on the basis of weeds and consequent biomass sampling.

DISCUSSION :

N. maculata cause a large negative impact on C. longiareolata populations. We attribute the negative association between the predator and prey at all sampling stations of Upper Lake.

During the peak population of Notonecta there is a declining population of the Dipterans was observed, thus hemipterans stabilizing an inverse relationship with Dipterans. This inverse relationship can be explained in terms of prey and predator interactions as the hemipterans were found to feed on the dipterans, such as Tendipes tendipes, Tendipes kiefferulus, Culiseta longiareolata and Dolichocephala irrora and eliminated the population of dipteran species. Chesson (1984) found that a congener, Notonecta hoffmani, attacked and broke up Culex egg rafts and that Culex females oviposited less in the presence of Notonecta.

Thus it appears that apart from D.O. the abundance and sparse populations of the hemipterans as well as the dipterans may not be solely due to dissolved oxygen but is due to interdependent food webs suggesting a strong cascading trophic interaction.

With regard to the concept of predation, it is generally believed that higher aquatic communities such as fishes and Urodeles are known to be important organising factors of community structure.

It has been suggested that the efficiency of predators to reduce mosquitoes in Lake water may decline with increasing nutrients. The impact of Notonecta maculata on culiseta populations may not be as great in more nutrient rich sampling stations of Upper Lake, where larval densities may be higher and Dipteran development should be faster (Blaustein & Kottler 1993). Thus in a system with a higher nutrient base, the efficiency of Notonecta to control Culiseta populations may decrease due to faster mosquito development rates or higher densities of mosquitoes. Similarly Walde (1995) found that predatory mites impact on phytophagous mite populations were reduced when nutrient levels were increased.

Notonecta species are generally most efficient at preying on pelagic species and less effective at praying on species associated with vegetation such as Tendipes tendipes, T. kifferulus. Moreover, Giller & Mc Neill (1981) have shown that N. maculata is an efficient predator in open water rather than vegetative water. These mosquitoes, being associated with the vegetation, appear to be able to coexist with N. maculata.

We conclude that Notonecta has a very large impact on Culiseta populations, then other mosquitoes. i.e. T. tendipes, T. kifferulus and D. irrorata, often driving them locally extinct while other mosquito such as T. tendipes can coexist presumably because they occupy vegetation. Our results also suggest that backswimmer N. maculata can be important organising factor of community structure.

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superficial figure of lion population: There is no truth to it

The Lion : Symbol of power and courage
Dr. Asma ALI [ECOLOGIST]

 
Lion: second largest cat in the world  is one of the most recognised animals. It has been extensively depicted in sculpture, painting, rhymes, stories, Literature, movies and on national flags.

Right from my childhood  I am so fascinated  with big cats.  I visited National Park many times in  search of lion  (Lion has been kept in  manageries since the time of the Roman empire), but  always my search ended in smoke.  Finally, years after I got this opportunity,  when I visited (Gujarat, India) national park, the same day I had to catch the train to Bhopal which is why I was making haste. Despite all the Hustle bustle I stuck with lion, yes... ITS SOUNDS ULTIMATE,  without further ado I can claim that if there is a king of the forest, THAT WOULD BE JUST A LION, an  Adversary warrior with ultimate strength and power.

Analysis says that around a hundred years ago there were likely as many as 200,000 lions living wild in Africa. In the Pleistocene, the Lion ranged throughout Eurasia, Africa and North America but today it has been reduced to fragmented population in sub-saharan Africa and one critically endangered population in western India.

Asiatic lion were observed ( in 1826 by Australian zoologist John N. Meyer), until the 19th century, in and around Saudi Arabia, Eastern Turkey, Iran, Mesopotamia and from east of the Indus river to Bengal and Narmada river in Central India. It has been listed as vulnerable on the IUCN Red list since 1996, because  populations of lions in Africa and Asian countries have declined by about 43% since the early 1990s. The 14th Asiatic lion census was conducted in May 2015 and lion population was estimated at 523 individuals again in August 2017 surveyors counted 650 wild lions, as lion restricted to the Gir Forest National Park and surrounding areas.

The Proliferation of lion  in Africa spanned most of the central rainforest zone and the Sahara desert. In 1960s North Africa termed as non- lion -zone. Although  no exact evidence are available of the decline of Lion, perhaps Habitat loss and conflicts with humans are the greatest cause for concern.

Africa has been conducted several  large and well managed areas for lion conservation and protection. Unfortunately their numbers are decreasing  swiftly due to disease and human interference. In the Republic of the Congo, Odzala- kokoua National Park  was among the most well managed protected area in the 1990s, by 2014 the lion population is considered locally extinct.

According to the International Union of the Conservation of Nature ( IUCN), every year approximately 600 lions are slaughtered for sport and 64% of those are killed by American Trophy hunter.

In 2015; IFAW, IUCN and Duke University published their data about lion population and estimation says , around 23,000 to 39,000 Lion are left in the world. The proposed numbers appears to be highly antiquated and factually incorrect. Just have a look-

Zimbabwe is supposed to have 1,362 lions. A recent survey of the huge Gonarezhou Park in the South indicated that only 33 lines remain.

    

 Proposed number of lion in Zambia have 2,349 but factually it is far from it. Based on researchers and Safari operators, it could be estimated that Zambia is loaded  with only 400 to 500 lions and abundantly present in the large nationally protected area of Kafue and Luangwas.

   

  It's difficult to put an exact number of wild lions, but after a long research  we can conclude that there are less than 1000 wild  lions  left in all of South Africa. It is sad to say that in West Africa lions are almost extinct. Only Tanzania, South Africa, Kenya, Zambia, Zimbabwe and Namibia  have a countable population of lion.  Ethiopia has only 50 wild lions. Uganda and Congo together only have less than 400 lions and in the other African countries there are no lion. So the total population of wild lions in Africa might be around 5,000 individuals.

Evolution and extinction of species is a natural process,  which we call the balance of nature , but this process is extremely slow. In the last 50 years we have manipulated our environment a lot, which can have very far reaching consequences. Water crisis,  pollution, natural disasters,  global warming and extinction of species is a warning sign,  that we should take drastic step to protect our environment. We have already constructed many laws for Wildlife Protection and sustainable development of environment but this is the time for enforcement and implementation.

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how is your equation with sea creatures?

Dr. Asma Ali (Ecologist)

Switch gears to sea bottom

How is your equation with sea creature?

At 5:52 pm ET Sunday ( 7:52 a.m. Monday, local time) arrival of James Cameron( director of Terminator, Titanic and Avatar) at the Mariana trench’s Challenger Deep, on the depth of 35,756 feet was enough to drag everyone's attention. James Cameron has become the first person to travel solo to the deepest point on Earth. Amazingly that's 120 times deeper than the Grand Canyon and a mile deeper than Mount Everest.

The whole event was recorded by Cameron on 3D camera and that would be turned into a feature film. Mr. Cameron was very much sure to collect as many samples of sea bottom, but due to the Harsh conditions he was not able to collect sample as he wanted to.

The ocean is a continuous body of saltwater that covers more than 70% of the Earth surface; the deepest point in the ocean is around 36,198 feet. Ocean currents govern the world's weather and agitate the Kaleidoscope of the ecosystem. The ocean holds about 321 million cubic miles of water which is roughly 97% of Earth's water supply.

The ocean floor is called the abyssal plain. Below the ocean floor, there are a few small deeper areas called ocean trenches.Features rising up from the ocean floor include seamounts, volcanic islands and the mid oceanic ridges and rises.

  The Mariana trench is located in the Western Pacific Ocean about 200 km east of the Mariana Islands; it is the deepest known Ocean trench on earth. It is crescent shaped and measures about 2,550 km in length and 69 km in width.

Researchers from Dalhousie University in Nova Scotia ,Canada ,believe that 91% sea creatures are still unknown to only 2,35,000 or so species we know about. According to Columbia university's Earth institute we know more about space than the ocean ,so in a sense ,a majority of the creatures lurking below the surface.

Three main obstacles have kept us from studying the depth of the ocean; absence of light, very cold temperature and high pressure. As you know light only penetrates the top 200 metres of the ocean ( the depth of the ocean can be as much as 11000 meters deep). Most places in the ocean are completely dark, which is impossible for human to explore without bringing a source of light with them.

Secondly, the ocean is very cold; colder than 0 degree Celsius (32 degree Fahrenheit ) in many places. Finally, the pressure increases tremendously as you go deeper. Scuba diver can rarely go deeper than 40 meters due to the pressure. The pressure on a diver at 40 meters would be 4 kilogram per square centimetre. Even though we don't think about it, the air in our atmosphere has weight. It presses down on us with a force of about 1 kilogram per square centimetre (14.7 lbs per square in).

In the ocean for every 10 metre of the depth, the pressure increases by nearly one atmosphere ! Imagine the pressure at 10,000 meter,that would be 1,000 kilogram per square centimetre (14,700 lbs/sq in) . Todays submarines usually dive to only about 500 meters to go deeper than this, they must be specially designed for greater depth (Lumen Earth Science: The ocean ‌).

Creatures that live thousands of feet below the ocean surface have developed special adaptations to survive. While some of them may look strange to us they have developed this appearance over thousands of years to help them thrive in their extreme environment. From qualities like bioluminescence to special resistance against the extremely high pressure in the deep sea, these animals have found a way to live in their otherworldly environment.

In fish alone there are about 1500 known species that have luminescence.For bioluminescence a species must contain luciferin, a molecule that reacts with oxygen to produce light. There are different types of Lucifer which vary depending.

Marine mammals such as whales, dolphins and seals have an amazing ability to hold their breath-sometimes for up to 2 hours, while they dive deep to search for food and evade predators. In the cold, dark waters hundreds of metre below the surface, animal rely heavily on sound to navigate, avoid danger and locate prey.

In the late 1990's researchers at the Woods Hole Oceanographic Institute (WHOI) invented the D-Tag ,radio device that can be attached by suction cups to a whales back to record depth, water temperature and other information.

                     

Generally the temperature at the surface of ocean found to be around 37 degree Celsius  vice versa bottom of the trench was only 2 degree Celsius. Because of the deepness; sunlight and warmth cannot penetrate, that makes Ocean bottom black and very cold. Pressure was also observed very high at the bottom. According to Cameron  its like having three big cars piled on your toes. This caused his capsule to shrink, making it even smaller.

When we see publicly available topographies of seafloor we feel it has covered almost all features of sea bottom and we can get the impression that the job of mapping the planet is over. Far from it, these representation often based on satellite estimates that is not enough to reveal sea bottom ecosystem.

Most of us think the bottom of the ocean is flat and dark and filled with mud or sand and is a happy hunting ground of fishes and octopus. No, it's not true, not all the ocean floor is made of Sand. The ocean floor consists of many materials and it varies by location and depth. It contains the largest mountain range on Earth, Canyon far grander than the Grand Canyon and towering vertical Cliff rising up three miles.

                 These days everyone taking an interest to know more about moon and solar system and obsessed with aliens ( here, I am not picking up the obsession of Tik -Tok………. take my apology in advance). It is very interesting to know that some of the strangest and most terrifying creature in the universe lie beneath the surface of our own planet. Let me introduce you to the most terrifying creatures of the ocean.

Dragon fish:

As the name suggests it is a large fish which actually started its life at the surface of the ocean as a result of its egg being buoyant. Dragon fish are found at a depth of 2 kilometre is capable of producing its own light, using a method, known as bioluminescence. It contains many light producing photophores, but one of them can be found on a barble attached to its lower jaw to attract its Prey for hunting.

Frilled shark:

Frilled Shark inhabits the depths of the Atlantic and Pacific oceans. Its large body proceeds to swallow its victim whole like a snake. Frilled shark also termed as living fossils.

Vampire squid:

The most distinguished feature of Vampire squid is its large Eyes ( largest eyes of any animals in the World), that Gives approval to live in the depths. Opposite to its name ‘Vampire’,  it doesn't suck blood, infact its tentacles barely have suckers at all. The name actually comes from intensely red eyes and clock like webbing.

Big red jellyfish:

It would be very scary to see a jellyfish over 1 metre in length with a  slide red coloration ( just opposite to a fascinating scene I watched in  movie LIFE OF PIE  where luminescent of multiple jellyfish drags you to fantasy world ).  The  tentacles of this deep sea jellyfish makes a series of fleshy ‘feeding arms’, to capture its prey.

Giant squid:

The Giant squid  has for centuries been a thing of legend. it found deep beneath the sea surface, mostly attacked by Sperm Whale, which is why Sperm Whales are   only real Predator of Giant Squid.  In fact the two are famous for their deep sea battles and their carcasses are often times found bearing the marks of mortal combat  on their bodies .

Pacific black dragon:

Every creature of the earth have their own speciality.  What do they eat? Where do they live?  and How do they behave with their entourage? make them surpassing.  Pacific black Dragon proofing it well. Being a deep sea Predator most of its Prey are bioluminescent, which is why its stomach specially designed to reduce or prevent light  from radiation.

 As we know, over 70% of Earth's surface is covered by ocean and we only know 3% of Underwater ( need to keep digging ).

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