162021 How ocean warming and acidification affect food webs

1/6/2021 How ocean warming and acidification affect food webs
| Ask A Biologist
https://askabiologist.asu.edu/plosable/marine-food-web-collapse
1/5
(https://asuforyou.asu.edu/?utm_campaign=asu_for_you&utm_c
ontent=partner_header_logo_link)
Learn more about ASU for You (https://asuforyou.asu.edu)
(/contact/askaquestion) (/about/teacher-toolbox) (/listen-
watch)
(/home)
Climate change: changes in the Earth’s weather that
scientists predict will happen over many years.
Industrial Revolution: a time of development from the
late 1700s to the mid-1800s that led to increased use of
machines, factories, and energy, and that resulted in
increased pollution....more
(https://en.wikipedia.org/wiki/Industrial_Revolution)
Ocean acidification: a reaction that occurs when there is
more carbon dioxide present in ocean waters than
normal due to an increase in carbon dioxide in the air.
Carbon dioxide can split into smaller ions, releasing
hydrogen ions into the water. This causes the water to
become acidic....more
(https://en.wikipedia.org/wiki/Ocean_acidification)

Productive: getting a lot done or providing a favorable
environment with food and shelter for many organisms
to grow.
Road diversion: a special route for use by traffic when a
road is temporarily closed or has restrictions.
Trophic flow: the transfer of energy between trophic
levels in a food web....more
(https://en.wikipedia.org/wiki/Energy_flow_(ecology))
Trophic level: a position in a food web, based on
relationships with other organisms in the food
web....more
(https://en.wikipedia.org/wiki/Trophic_level)
Vibrant: bright, or brightly colored.
Countdown to Disaster in Marine Food Webs?
Written by: Tin Hang (Henry) Hung
show/hide words to know
What's in the Story?
It’s noon and your stomach starts rumbling—you’re hungry.
You want to get some Japanese ramen for your empty stomach.
Stepping out of your house, you are hit by a wave of heat.
https://asuforyou.asu.edu/?utm_campaign=asu_for_you&utm_co
ntent=partner_header_logo_link
https://asuforyou.asu.edu/
https://askabiologist.asu.edu/contact/askaquestion
https://askabiologist.asu.edu/about/teacher-toolbox

https://askabiologist.asu.edu/listen-watch
https://askabiologist.asu.edu/home
https://en.wikipedia.org/wiki/Industrial_Revolution
https://en.wikipedia.org/wiki/Ocean_acidification
https://en.wikipedia.org/wiki/Energy_flow_(ecology)
https://en.wikipedia.org/wiki/Trophic_level
| Ask A Biologist
2/5
What would happen if the fish we rely on
for food was no longer available? Image
by Douglas Perkins.
(/sites/default/files/resources/plosable/Marine_Food_Web/carbo
n-
emission-by-region.png)
Global carbon emissions, in the 1800s
and 1900s. Click for more detail.
(/sites/default/files/resources/plosable/Marine_Food_Web/marin
e-ecosystem.png)
“Maybe I should get a cold lunch like sushi instead,” you think.
“Hot ramen may not be good
on this hot day.” Other people had the same idea, and the
restaurant has already sold all of
its sushi for the day. You go off to find something else that is
cold for lunch.
Weather often affects your food choice. You might drink more

hot chocolate in the winter,
and eat more ice cream in the summer. Something similar can
happen in the sea. When
temperatures warm up, some organisms may be found in greater
numbers. Changes like
these impact what is being eaten in the ocean. But what would
happen if an organism was
“sold out” in the sea?
Researchers discuss how the changing climate can alter the
feeding relationships in the sea
in the PLOS Biology article “Climate Change Could Drive
Marine Food Web Collapse
Through Altered Trophic Flows and Cyanobacterial
Proliferation
(https://journals.plos.org/plosbiology/article?id=10.1371/journa
l.pbio.2003446).” They may have some sad news – the marine
food web could collapse. And the clock is ticking.
Hot and Acidic Oceans?
Standing in a corn field, you see a machine drive by, picking
corn off the plants. A lot of work
that used to be done by hand is now done using machinery. This
trend started in the late
1700s and increased heavily by the 1900s. The increase in
machines and power usage was
called the Industrial Revolution. All of this production put off a
lot of air pollution.
After the Industrial Revolution, the amount of carbon dioxide
(CO ) in air rose drastically.
This increase in CO caused many problems in today’s world,
including two big ones:
climate change and ocean acidification. Because of these
changes, our oceans are getting

warmer and more acidic. How will this affect relationships in
the sea?
A Taste of Trophic Levels
Species are highly connected to one another. The changing
climate can alter their
relationships. To understand how these relationships change,
let’s look at how we divide organisms in a food web. Different
levels
of the food web, or food chain, are called trophic levels.
“Trophic” just means related to eating. So let’s look at the
different eating
levels of a web.
Primary producers (like plants) are at trophic
level one. They use sunlight to make sugars
to feed themselves. The next level has
herbivores, or plant eaters. These include
large animals like deer, and tiny animals, like
zooplankton. The third level is filled by
animals that eat other animals. For example,
small fish eat zooplankton. Some food webs
have a higher levels, with predators that eat
animals from the level below.
In these feeding relationships, the energy
stored in prey flows to predators, up through
trophic levels. This is known as a trophic
flow. And because each organism may have
multiple food choices, a food web is created,
instead of just specific food chains.
2
2

https://askabiologist.asu.edu/sites/default/files/resources/plosab
le/Marine_Food_Web/carbon-emission-by-region.png
le/Marine_Food_Web/marine-ecosystem.png
https://journals.plos.org/plosbiology/article?id=10.1371/journal.
pbio.2003446
| Ask A Biologist
3/5
A food web showing the feeding relationships among organisms
in the Canadian arctic. Note
that some species have more than one food choice (e.g. narwals
eat fish (cod) and benthic, or
ground dwelling, invertebrates). Also note that some species are
a common food choice to
more than one predator (e.g. cod are eaten by seabirds, seals,
and some whales). Image from
"Current State and Trends in Canadian Arctic Marine
Ecosystems II," by Darnis et al., in Climatic
Change. Click to enlarge.
(/sites/default/files/resources/plosable/Ma
Mesocosms can be built on land to hold
water, or they can be created in the
marine environment. Click for more
detail.
(/sites/default/files/resources/plosable/Marine_Food_Web/energ
y-

flow-graph.jpg)
How did the treatments affect energy
flow between levels of the food web?
Click for more detail.
Humans are part of marine food webs, as
marine organisms, like fish, are part of our
diet. Billions of people depend on fish for
nearly one-fifth of the animal proteins they
eat. With such a dependence on marine food
webs, we need to understand how the
changing climate may affect the oceans.
Studying Mini Marine Worlds
Researchers built 12 mesocosms to study how changing climate
affects marine food webs.
The word “mesocosm” comes from two Greek words: meso–
means “medium”, and –cosm
means “world”. They are “medium worlds” that researchers
build, with habitats and
organisms inside. Researchers can then experiment within these
man-made worlds. For
this study, the mesocosms were about the size of a hot tub,
which holds around 1,800 liters
of water (almost 500 gallons).
The researchers split the mesocosms into four groups, or
treatments. In the first, they
matched current conditions in the ocean. In the second, they
increased the CO level to 900
ppm (“OA” treatment). In the third, they increased the
temperature by 2.8°C (“T” treatment).
And in the last, they combined those CO and temperature

increases (“OAT”). They also
called OAT the “business-as-usual” condition, as this is where
our environment will end up in
the year 2100 if we keep polluting as much as we do now.
Altered Trophic Flows: Road Diversions
Researchers treated the mesocosms for over four months, and
measured the effects on the amounts of plants, invertebrates,
and
fish. They weighed the organisms at different trophic levels.
Then they determined the energy flow by comparing the weights
among levels.
Together, warming and higher acidity decreased energy flow
from the producers (trophic
level one) to the herbivores (level two). Warming also reduced
energy flow to higher trophic
levels. There were clearly some changes or “barriers” that
slowed energy flow between
trophic levels.
Researchers also found that the combination of warming and
acidity increased the energy
stored (known as biomass) in producers. More plants? It sounds
like good news, right?
However, this combination could decrease biomass at higher
trophic levels. Researchers
found that although there was more energy in producers,
organisms in higher trophic levels
could not use the extra energy. This is why energy flow among
the trophic levels was
reduced.
Energy can neither be created nor destroyed. Energy in
producers must end up somewhere

else, if it is not available to higher trophic levels. These altered
energy paths are like road
diversions in your city. The carriers cannot efficiently deliver
the goods to the receivers, and
the energy ends up on a different route.
But what makes this happen? What are the “diversions” that
keep this energy from moving through the food web as it would
usually?
Cyanobacteria Takes Over
2
2
le/Marine_Food_Web/mesocosms.jpg
le/Marine_Food_Web/energy-flow-graph.jpg
| Ask A Biologist
4/5
(/sites/default/files/resources/plosable/Ma
cover.jpg)
How did ocean acidification and
warming affect bacteria and algae? Click
for more detail.

Cyanobacteria (blue-green algae) are bacteria that capture
sunlight and make food. They are producers, in the first trophic
level.
However, to avoid being eaten, some cyanobacteria release
toxins that can kill. Because of this, most herbivores prefer
another
food choice, turf algae.
In this study, researchers found that cyanobacteria grew better
in warmer waters. But
herbivores did not eat these cyanobacteria. This means more
food was produced at trophic
level one, but the energy did not flow to trophic level two or
beyond.
Meanwhile, carnivores at higher trophic levels needed to eat
more herbivores, because they
had higher energy demands in warmer water. Herbivores were
sandwiched; they ate less,
but were eaten more. The death of herbivores eventually could
no longer support the food
web. The energy in uneaten cyanobacteria built up at the base of
the food web, and
organisms at higher levels didn’t have enough food to survive.
No More Business as Usual
In this way, future warming could very likely cause marine food
webs to collapse.
Considering how much we depend on fish, that’s a scary
thought. If we don’t change our
ways, and reduce our carbon emissions, our oceans may soon be
less productive and
vibrant than they are now.
Additional images via Wikimedia Commons. Coral reef by US

Fish and Wildlife Service - Pacific Region. Coral reef at
lighthouse by
Holobionics.
View Citation
You may need to edit author's name to meet the style formats,
which are in most cases "Last name, First name."
Bibliographic details:
Article: Countdown to Disaster in Marine Food Webs?
Author(s): Tin Hang (Henry) Hung
Publisher: Arizona State University School of Life Sciences Ask
A Biologist
Site name: ASU - Ask A Biologist
Date published: January 4, 2019
Date accessed: January 6, 2021
Link: https://askabiologist.asu.edu/plosable/marine-food-web-
collapse
APA Style
Tin Hang (Henry) Hung. (2019, January 04). Countdown to
Disaster in Marine Food Webs?. ASU - Ask A Biologist.
Retrieved January 6,
2021 from https://askabiologist.asu.edu/plosable/marine-food-
web-collapse
American Psychological Association. For more info, see
http://owl.english.purdue.edu/owl/resource/560/10/

(http://owl.english.purdue.edu/owl/resource/560/10/)
Chicago Manual of Style
Tin Hang (Henry) Hung. "Countdown to Disaster in Marine
Food Webs?". ASU - Ask A Biologist. 04 January, 2019.
For more info, see
le/Marine_Food_Web/cyanobacteria-cover.jpg
| Ask A Biologist
5/5
MLA 2017 Style
Tin Hang (Henry) Hung. "Countdown to Disaster in Marine
Food Webs?". ASU - Ask A Biologist. 04 Jan 2019. ASU - Ask
A Biologist, Web.
6 Jan 2021. https://askabiologist.asu.edu/plosable/marine-food-
web-collapse
Modern Language Association, 7th Ed. For more info, see

Client:
Date Prepared:
Project:
Site Address:
- Contact Information:
Local Address:
Office Telephone:
Contact Names / Position:
Contact Telephone
Contact Mobile Tel
-

Updated 10/7/2013 HEALTH AND SAFETY
Page 1 of 20
SITE SPECIFIC SAFETY PLAN
Project Name and Number
Purpose:
The purpose of this method statement is to define the safe
methods and procedures to be used by -------
------------ and subcontractor personnel for this noted project
places the highest priority on
ensuring full compliance with all applicable safety procedures
on every project. While jobsite safety is of paramount
importance to on an ethical level, it is also apparent that jobs
with the best
overall safety records tend to be the most profitable.

This method statement will apply to all persons associated with
the works at the referenced site and to all persons who by nature
of their involvement with this project interface directly or
indirectly with this work.
Safety Responsibilities
· All persons will;
· All Project Management will ensure;
HEALTH AND SAFETY
Page 2 of 20
· Project Supervision shall

· Subcontractors
All Subcontractors shall:
Emergency Action Plan:
1. The emergency action plan for this project is as follows:
Competent Person:
The term “competent person” is used in many OSHA standards.
The definition of a competent person, by OSHA standards, is
one who “is capable of identifying existing and predictable
hazards in the surroundings or working conditions which are

unsanitary, hazardous, or dangerous to employees, and who has
authorization to take prompt corrective measures to eliminate
them”. (29 CFR 1926.32(f)). While there are specific standards
which require a specially trained individual designated to
oversee a specific work practice as a “competent person”, all
employees must be trained in hazard recognition techniques and
all have the authority to stop work in the event of a hazardous
situation.
The activities which a designated and DOCUMENTED
competent person according to OSHA standards will be assigned
are as follows:
·
HEALTH AND SAFETY
Page 7 of 20
Responsible Person
Additionally, assigned “responsible” persons will be assigned

for the following activities: 1.
These “Responsible Persons” will have documentation that they
possess the training, knowledge, skills and abilities to perform
the assigned functions.
Scope of Work:
Logical Sequence of Task:
1.
HEALTH AND SAFETY

of 20
SPECIFIC SITE SAFETY RULES:
1.
Schedule:
Proposed Start Date:
Duration:
Working Hours:
Overtime Hours:
Access to Work Area:

HEALTH AND SAFETY
Resources Required to Undertake Works:
Contractor, Equipment, Materials:
Inspections / Documentation Required:
· .
Personal Protective Equipment (PPE):

All employees and subcontractor employees will use and wear
approved PPE as follows :
·
Disposal of contaminated PPE
First Aid, Emergency and Treatment Arrangements:
1.
Medical Facilities Identified for this Project:
Occupational Clinic Name:
Address:
Telephone:
Working Hours:

~ Map~
Emergency Medical Facilities Identified for this Project:
Emergency Hospital Name:
Address:
Telephone:
Working Hours:

~Map~
Monitoring & Compliance
Monitoring and compliance of the work by ---------
*** Include Emergency Action Procedures and Site Map
Subject
Required
Specific & detailed information / description required for all
questions.
List OSHA Standard Number
Yes
No
Compressed Gas:
N/A
Will cylinders be brought on site?

Are there plans for safe use and storage on site?
Will portable torch sets be required?
(All gas cylinders and welding machines must be left outside of
excavations and
long enough leads provided.)
Subject
Required
questions. List OSHA Standard Number
Yes
No
Ladders:
N/A
Will ladders be required?
(All ladders – min 300 lb. rating.)
The ladder chosen must be long enough to provide access to the
work area without necessitating standing
on the top two steps of a stepladder
or the top three rungs of a straight ladder.

Will fall protection be required? List equipment to be used.
Subject
Required
Yes
No
Fall Protection, Leading Edge Work & Elevated Surfaces:
N/A
Has a Fall Protection Rescue Plan been developed?
Attach and describe plan.
Will fall protection be required? 100% protection > 6 feet.
Are competent/qualified persons identified to perform system
and equipment inspections,
identify hazards, and anchor points as needed?

Subject
Required
Yes
No
Cranes and Rigging:
N/A
Will crane operations be required?
Have all overhead lines been identified and the locations
appropriately communicated?
Will any special lifting devices be needed?
Will any Critical Lifts take place?

Has all rigging equipment been inspected?
Is all equipment appropriate for the task(s)?
Have all required safety inspections been completed?
Will traffic control be provided (pedestrian & vehicular)?
Subject
Required
Yes
No
Confined Spaces:
N/A
Will any confined space work be performed?
**NOTE: Atmospheric testing must be conducted daily prior to
entry into a Confined Space.

Will any Confined Space Entry permits be required?
Have affected personnel been trained for confined space entry?
What equipment will be provided for non-entry rescue?
Will external rescue team services to be used?
Please specify the name of the provider.
Have all entry procedures been provided and documented?
Subject
Required
Yes

No
Excavations (all soil will be classified as type C):
N/A
Will equipment to be brought on site? Please specify type.
Will any work activities involve excavations greater than four (
4) feet?
Will a trench box/shoring be needed?
Does fencing/barricade need to be installed?
Daily inspections of excavations, adjacent area and protective
systems for evidence that result in cave-in, failure of protective
systems, hazardous atmospheres or other hazardous conditions
must be conducted before the start of work and as needed
throughout the shift. Inspections must be
documented.
What will be the
MAXIMUM depth(s) of the

excavation(s)/trench(s) be on this project?
Subject
Required
Yes
No
Mobile Equipment / Powered Industrial Trucks /
Lifts / Booms:
N/A
Will any mobile powered equipment be required? Type to be
brought on site?
Will you be using any special attachments? ex. jibs, man lifts,
etc.
Are operators trained / certified for operations of equipment?

Is there a plan for fuel transfer/storage or battery changes?
Subject
Required
Yes
No
Caught-In / Struck-By Hazards:
N/A
Are employees familiar with pinching and crushing
points?
Are employees aware of the hazards associated with overhead
loads and swing radius?
Are all vehicles equipped with appropriate back- up alarms,
horns and lights?

Subject
Required
Yes
No
Hand and Power Tools:
N/A
Will all grinders, saws and similar equipment provided with
appropriate safety guards?
Are power tools used with proper shields, guards, or
attachments, as recommended by the
manufacturer?
Power tools must be equipped with a constant-pressure switch
or
control that shuts off the power when pressure is
released.

Will all cord-connected, electrically operated tools and
equipment be properly grounded or of the
approved double insulated type?
Additional Focus Areas:
Subject
Required
Yes
No
Personal Protective Equipment:
N/A
What type of PPE will be used for this project?
Will any special PPE be required, i.e. respirators? What type?

Have portable eye wash stations been set up on the jobsite?
Has personnel received training for special PPE
requirements? NOTE: Hi Vis clothing is required.
Is there verification of medical respiratory protection clearance
submitted / attached?
Will respirators be worn on a voluntary use? (Half mask, paper,
etc.)
Subject
Required
Yes
No
Signs, Signals and Barricades:
N/A
Describe site control measures, especially in high public areas
such as playgrounds, parks, etc.

Will perimeter barricades be used?
Will any caution/danger signs be needed?
Will flammable gas/liquid labels be needed? Will material
labels be needed? GHS
Will traffic control be provided?
Subject
Required
Yes
No
Additional Work Permits:
N/A

Will any utility interruption permits be required?
Will Hot Work (welding/cutting/grinding/ soldering/electrical)
permits be required?
Subject
Required
Yes
No
HAZARD COMMUNICATION
N/A
Are all employees trained in Hazard Communication / GHS?
Are all Safety Data Sheets provided and a copy easy to obtain at
job site? Where are they located?

Are employees trained to handle/use specific materials?
Does storage and use meet all NFPA, Federal and State
Regulations?
Subject
Required
Yes
No
Hot Work:
N/A
Are hot work activities to be performed?
(Any flame or spark producing task.) Briefly describe.
Will any special PPE be required?
Will fire blankets/protective shields/screens be required?

Are fire watch personnel current with actual training?
Subject
Required
Yes
No
Flammable Gases / Liquids:
N/A
Will any flammable gases and/or liquids be used?
Have provisions for their storage been made?
Will appropriate containers be utilized? Safety cans are
required.
Are secondary containment and spill kits required?

Subject
Required
Yes
No
Emergency Preparedness:
N/A
Have the appropriate number of fire extinguishers been
identified? Inspections will be performed monthly.
Have emergency phone numbers been identified?
Have adequate security measures been identified?
Has an emergency evacuation plan been developed?

Will emergency responders have easy access if needed?
Subject
Required
Yes
No
Housekeeping and Waste Management:
N/A
All projects are to be maintained clean, sanitary and orderly.
Is there a plan for waste disposal in place?
Are all characterization, containerization, segregation, storage
and disposal
requirements understood?

Is there a plan for water/wastewater discharges in place?
Describe or attach plan.
Is there a spill plan in place?
JOB HAZARD ANALYSIS (JHA) – LIST AT LEAST 3
ACTIVITIES
1. Contract Number:
2. Contractor Name:
3. Date prepared:
4. Title/Activity Performed:
5. Start Date
6. Estimated Date of Completion:
7. PRINCIPAL STEPS
8. POTENTIAL HAZARDS
9. RECOMMENDED CONTROLS
· Form and pour columns
·
·
·
·
·
·
10. EQUIPMENT TO BE USED
11. INSPECTION REQUIREMENTS

12. TRAINING REQUIREMENTS
13. Prepared by (Signature and Date):
14. Safety Officer Review (Signature and Date):
15. AHA Discussed at Preparatory Meeting Held On (Signature
and Date):
Acknowledgement:
Person Drafting this Method Statement
Name:
Position:
Date:

Acknowledgement of Project Team
I confirm that I have read the above method statement and fully
understand the work to be carried
out:
Sign:
Print:
Date:
Sign:
Print:
Date:
Sign:
Print:
Date:
Sign:

Print:
Date:
Sign:
Print:
Date:
Sign:
Print:
Date:
Sign:
Print:
Date:
Sign:
Print:
Date:

Sign:
Print:
Date:
Sign:
Print:
Date:
I CONFIRM THAT THE APPROPRIATE CONTROLS ARE IN
PLACE. I HAVE INCLUDED ONLY ACTIVITIES AND
CONTROLS THAT ARE RELEVANT TO THIS ASSESSMENT
SIGNATURE OF MANAGER/SUPERVISOR:
…………………………………………………………………
PRINT NAME: DATE:
………………......

/
The Washington Post
Health & Science
Decline of predators such as wolves throws food chains out of
whack, report says
By Darryl Fears
July 14, 2011
The decline of large predators such as big cats, wolves, sharks
and giant whales may be “humankind’s most
pervasive influence on the natural world,” causing prey animals
to swell in population and throw food chains
out of balance, a new report says.
Humans have touched off the world’s latest mass extinction,
according to the report, published Thursday in
the journal Science, and the consequences are being felt on land
and in water systems as large predators
vanish.
“Recent research suggests that the disappearance of these
animals reverberates further than previously
anticipated,” says the report, “Trophic Downgrading of Planet
Earth.” In addition to creating an
overabundance of prey, the dwindling number of predators
contributes to the spread of disease, wildfires and
invasive species.

The decline of wolves in Yellowstone Park is cited as an
example of what can happen. Elk and deer in the park
once flourished on willow trees and saplings, threatening a
crucial part of the forest on which other creatures
rely.
The report also mentions the slaughter of lions and leopards by
hunters and herders in parts of sub-Saharan
Africa. As a result of the killings, disease-carrying olive
baboons have thrived without their top predators and
inched closer to food crops and people.
The decimation of sharks along the U.S. Atlantic Coast has
allowed their main prey, the cow-nosed ray, to
proliferate and dine heavily on the threatened Chesapeake Bay
oyster.
A reduction of big herbivores such as buffalo and wildebeest in
East Africa through hunting is also a problem,
the report says. Their demise has led to increases in plants that
fuel giant wildfires in the dry season.
Americans don’t have to visit federal parks or sub-Saharan
Africa or plunge into seas to see the consequences,
said Ellen K. Pikitch, a co-author of the report and a professor
at Stony Brook University in New York. Many
experience the problem every day in their own back yards.
“People who live in North America know it’s hard to grow a
garden because deer will eat it,” said Pikitch, a
marine biologist. “The lack of wolf populations throughout
North America has led to an expansion of the deer
https://www.washingtonpost.com/national/health-science
https://www.washingtonpost.com/people/darryl-fears/

http://www.sciencemag.org/content/333/6040/301.abstract
http://www.somas.stonybrook.edu/people/pikitch.html
/
population.
“You may hate wolves. You might think they’re dangerous. But
without them, the land changes,” Pikitch said.
“Deer carry ticks. We humans become more susceptible to
diseases such as Lyme disease.”
Wildlife advocates say efforts to protect one species of predator
in the United States were set back when the
Obama administration signed a bill in April that removed 1,300
wolves from the endangered species list in
northern Rocky Mountain states. It was the first time Congress
had taken a species off the endangered list.
The law allows limited hunting of the animals to begin this
summer.
Other studies have examined the collateral damage caused by
the near-extinction of large predators and
herbivores. But the report in Science is the first to tie together
the impact on land animals as well as salt and
freshwater marine life, Pikitch said. It was conducted by an
international team of 24 scientists and funded
primarily by the Institute for Ocean Conservation Science at
Stony Brook.
Much of the science in this area of study has focused on the
threat to life at the bottom of the food chain,
theorizing that small animals and plants are important because
so many creatures rely on their survival.

Although “bottom-up” research is fundamental and important,
the report says, “top-down” research deserves
wider consideration “if there is to be any real hope for
understanding and managing the workings of nature.”
The report acknowledges that top-down research of the food
chain is difficult to conduct, noting that it can
take decades to measure the effects of the disappearance of
large predators.
“The irony . . . is that we often cannot unequivocally see the
effect of large apex consumers until after they
have been lost” and the ability to restore the species has also
been lost, the report says.
Large predators, or apex species, include animals that people
adore, such as otters, and others not so popular,
such as vultures.
On the Pacific Coast, from Alaska to the southern tip of
California, sea otters were hunted in the 1900s to
near-extinction for their pelts. Their absence started a chain of
events that nearly eliminated the kelp forests
that nurture all manner of marine life on the coast.
Sea otters feed on sea urchins, which dine on kelp. Without
otters, the sea urchin population exploded. The
kelp forest started to disappear. When sea otter populations
elsewhere were re-introduced to a few areas
along the coast, the kelp started to rebound.
A telling consequences of the absence of large predators can be
found on the Scottish island of Rum, where
wolves have been gone for more than 250 years and red deer
thrive, the report says. The once forested island
is now treeless.

http://www.washingtonpost.com/politics/1300-wolves-to-come-
off-endangered-list/2011/04/17/AFXR7LwD_story.html
/
Darryl Fears
Darryl Fears is a reporter on the national staff who covers the
Interior Department, issues affecting wildlife and the
Your support helps our journalists report news that matters.
Try 1 month for $10 $1
Already a subscriber? Sign in
https://www.washingtonpost.com/people/darryl-fears/
https://twitter.com/bydarrylfears
https://subscribe.washingtonpost.com/acquisition/?promo=ba_d
_am_2&acqEntType=mktg_onsite_article

162021 How ocean warming and acidification affect food webs

Recommended

Recommended

More Related Content

Similar to 162021 How ocean warming and acidification affect food webs

Similar to 162021 How ocean warming and acidification affect food webs (12)

More from KiyokoSlagleis

More from KiyokoSlagleis (20)

Recently uploaded

Recently uploaded (20)

162021 How ocean warming and acidification affect food webs