Science Learning Packet BIO B: Population Ecology, Lessons ...

Science Learning PacketBIO B:

Population Ecology, Lessons 1-2 science learning activities for SPS students during the COVID-19 school closure.

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Due to the COVID-19 closure, teachers were asked to provide packets of home activities. This is not intended to take the place of regular classroom instruction but will help supplement student learning and provide opportunities for student learning while they are absent from school. Assignments are not required or graded. Because of the unprecedented nature of this health crisis and the District’s swift closure, some home activities may not be accessible.

If you have difficulty accessing the material or have any questions, please contact your student’s teacher.

Unit Driving Question: Why has the orca population declined in Puget Sound? How can we protect orca populations in the future?

Day Activity Extensions (if interested and time allows)

1

1 Population Ecology Initial Ideas PowerPoint lesson (larger copies of data sets available)

Discussion 00 Learning Tracking Tool

2

Start: 2 Who are the Orcas PowerPoint lesson (larger copies of images and website texts available)

2 Who are the Orcas Student Worksheet 2 Task A Identifying Orca Whales 2 Task B Graphs 2 Task B PCB Article 00 Learning Tracking Tool

3 Finish: 2 Who are the Orcas materials listed above

4

3.1 Stakeholder Articles PowerPoint lesson 3.1 Stakeholder Article Notes 3.1 Stakeholder Article Notes KEY Choose at least two articles:

3.1 Article Gov Inslee Bill_AP 3.1 Article Pacific Northwest Orca Population Hits 30_Smithsonian 3.1 Article SRKW-policy-brief_Jan2019 3.1 Article This land is your land _The Guardian

00 Learning Tracking Tool

You might want to spend an extra day reading more articles and/or this additional article: 3.1 OPTIONAL Hostile Waters Seattle Times Article

5

3.2 Human Impact HIPPCO PowerPoint lesson (website texts available)

3.2 HIPPCO Note-taking Guide 00 Learning Tracking Tool

You might want to spend an extra day reading and watching videos from the suggested resources.

6

4 Project Introduction 4 Orca Project Rubric for Distance Learning 4 Orca_Recovery_Task_Force_Recommendations 00 Learning Tracking Tool

7 5.1 Orca Food Webs

(food web pictures available) 00 Learning Tracking Tool

8 5.2 Keystone Species 00 Learning Tracking Tool

9

6.1 and 6.2 Project PowerPoint lesson 6.1 Orca Project Planning Worksheet Refer to: 4 Orca Project Rubric for Distance Learning 4 Orca_Recovery_Task_Force_Recommendations

As an extra challenge, you could include a second Orca Task Force recommendation in your project.

10 Continue 6.1 Project Work

11 Continue 6.1 Project Work

12 6.1 Present Your Project!

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ENVIRONMENT

BY SIMON LITTLE CKNW

Posted August 12, 2018 2:25 pm Updated August 13, 2018 11:20 pm

After more than two weeks and 1,500 kilometres, an apparent mourning ritual by an endangered orca has come to an end.

J35, known to some as Talequah, was spotted near San Juan Island on Saturday without her dead calf for the first time in at least 17 days.

Her calf was born and died on the same day, July 24.

The endangered southern resident killer whale had been keeping the carcass afloat, and pushing it with her as she travelled with her pod.

That had raised concerns among some scientists about her health and well -being, particularly since it was interfering with her feeding.

But Ken Balcomb with the Centre for Whale Research said J35 appears both healthy and

1:44Scientists give sick J50 orca first round of treatment

have lost a sig

whale-two days ago of J35 without her calf in the Georgia Strait near Vancouver.

It added that the carcass likely sank to the bottom of the Salish Sea, and researchers may not get a chance to perform a necropsy.

restoration is essential to

2:17A cross-border effort is underway to save ailing orca

A cross-border effort is underway to save ailing orca

Orcas as a species are not endangered, but J35 is a member of an endangered sub -population known as the southern resident killer whales. Just 75 of the animals remain.

Orca calf mortality is naturally quite high, ranging from 50 to 75 per cent, but Balcomb said it appears to be getting worse. The last successful birth by a southern resident was in 2015.

A joint U.S.-Canadian effort by scientists and veterinarians remains underway to save another critically ill orca in the southern resident J-pod.

-and-a-half-year-old has a serious infection.

A team was able to deliver a dose of antibiotics by dart on Thursday, and collect a breath sample which is currently being analyzed.

young age and calfbearing potential.

With files from the Canadian Press

© 2018 Global News, a division of Corus Entertainment Inc.

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Name _______________________________ Teacher _________________ Date __________

2 Who are the Orca Whales? You will complete 3 different tasks to learn about orca whales (Orcinus orca). In conclusion you will be able to describe how what orcas look like at the four benchmark scales: large, macro, micro and atomic-molecular scale.

Task A: Orca Ecotypes, Anatomy and Structure a. What is an Ecotype? Ecotype or subspecies is any of the socially and genetically distinct types of

orcas, defined by diet, calls and social organization. In the North Pacific, the three ecotypes are resident, transient and offshore. Review the infographics and visit the following websites to explore the three ecotypes in the North Pacific. https://us.whales.org/whales-dolphins/meet-the-different-types-of-orcas https://roaring.earth/the-10-types-of-killer-whales/

Orca Ecotype Geographic Range Food Behaviors Other Physical Differences

Resident - Northern

Resident - Southern

Transient

Offshore

b. Identifying Orca Whales: 2 Task A Identifying Orca Whales.

questions.

1. Why is it important to be able to identify individual orca whales?

2. What are some of the distinguishing characteristics that scientists use to identify orcas?

3. How do male and female orcas differ in their appearance?

4. Why is it easier for researchers to identify the mother of a new calf, rather than the father?

Task B: Orca Feeding Behavior a. Read Scholastic Science News: What's Killing Killer Whales? How banned

chemicals lingering in ocean waters are hurting orcas b. Review :

Mortality and Abundance Index for S. Resident Killer Whales and Chinook Salmon Orca PCB Poisoning

c. How can environmental pollution affect animal populations?

d. Make a claim for the Mortality and Abundance Index for S. Resident Killer Whales and Chinook Salmon graph. Use quantitative data to support the claim.

e. Cite evidence from the text and graphs to explain why orca whales likely have higher levels of PCBs than any other animal.

f. Write an assessment question to be used to quiz the class on Orca Feeding Behavior.

Task C: Orca Communication a. What is echolocation? Orca whales produce whistles, echolocation clicks, pulsed calls, low-frequency

pops, and jaw claps. An orca whale makes sounds by moving air between nasal sacs in the blowhole region. ... A tissue complex in a toothed whale's nasal region, called the dorsal bursa, is the site of sound production.

Review the following websites to learn more: https://seaworld.org/animals/all-about/killer-whale/communication/ https://orcaspirit.com/2015/12/how-does-echolocation-work/

Draw a picture to describe how echolocation works in orca whales:

b. Sounds in the Puget Sound Orca Sounds you will need a way to play sound (phone or computer speaker or headphones)

Listen to sounds of orca whales in the San Juan Islands http://live.orcasound.net/ Listen to the distinct sounds of different orca pods

http://www.orcasound.net/learn/learn-the-favorite-calls-of-the-southern-resident-killer-whales-j-k-and-l-pods/

Listen to other sounds in the Puget Sound http://listen.orcasound.net/PracticeHere/SamplesofOtherSounds.aspxNow test yourself with the easy, challenge and expert level quiz here can you detect the sounds? http://listen.orcasound.net/PracticeHere/TestYourselfEasyLevel.aspx

Summary Write a 3-4 sentence summary about your learning about the different sounds in the Puget Sound.

c. Noise Pollution and Whale Behavior. Run the simulation http://noaacontent.nroc.org/lesson13/l13la2.html

Summary Write a 3-4 sentence summary about your learning about the simulation.

Killer Whales: Could You Tell the Difference Between 10 Types?

by Teddy Fotiou

You might think of orcas as one distinct species, but there are actually 10 different types of these beautiful beasts and they all lead surprisingly different lives.

s largest dolphin species; and like other dolphins, they travel and hunt together in pods.

For centuries, these massive marine mammals have been considered homogeneous and, currently, are all classified under species Orcinus orca. Yet, over the past few decades, researchers have uncovered an incredible diversity among these cetaceans, and have separated them into ecotypes based on their appearance, range, and behavior.

Currently, scientists have identified ten orca ecotypes distributed across the globe. Some of these types share ranges with others, but they rarely interact and do not interbreed. This means that some (if not all) of these orcas should be classified as different species or subspecies.

The ten orca types are evenly split between the northern and southern hemisphere. In the northern hemisphere, orcas e, orcas are

Northern Hemisphere

In the Northern Hemisphere, the three most well-studied killer whale populations reside in the North Pacific, but there are also two other types in the North Atlantic.

Resident Orcas

Resident orcas are native to the North Pacific and are named because of their tendency to have small home ranges around areas of large fish populations. The majority of these orcas almost exclusively feed upon salmon, but some populations eat mackerel, halibut, and cod as well.

In the United States North Pacific, resident orca populations are classified into four groups: southern residents, northern residents, southern Alaska residents, and western Alaska North Pacific residents. Each of these populations have distinct genes, calls, and even culture, not unlike the variety of languages and cultures present in humanity.

Biggs orcas are also known as transient orcas, and they primarily prey upon other marine mammals. Whales, dolphins,

Southern California to the Arctic Circle, in search of their prey. Often, their range will overlap with that of the resident orcas.

Offshore Orcas

Living far out at sea, offshore orcas are rarely seen, and thus, the least observed and understood of the orca types. They generally occur 9 miles (15 kilometers) away from shore but are occasionally are seen near the coast.

B

These are the smallest and most widely distributed of the three North Pacific orcas, and they congregate in enormous pods. Generally, they are found in pods consisting of 20-75 orcas, but pods containing as many as 200 orcas are sometimes sighted.

Like resident orcas, offshore orcas are believed to primarily feed upon fish and sharks. This is because their teeth are rather blunt and worn, suggesting they consume prey with rough skin.

North Atlantic Type 1

Residing around Norway, Scotland, and Iceland, North Atlantic Type 1 orcas are generalist feeders. They mainly eat fish, such as herring and mackerel, but they will eat seals as well. Their teeth are small and blunt, which correlates with their preference for fish, and they will often herd huge schools of fish into dense balls, where they can easily capture them.

North Atlantic Type 2

North Atlantic Type 2 orcas are distinct from Type 1 orcas because of their diet. While North Atlantic Type 1 orcas prefer fish, Type 2 orcas primarily feed upon whales and dolphins, especially minke whales. This is particularly evident in their teeth, since Type 2 orcas have much bigger and sharper teeth than Type 1 orcas.

Southern Hemisphere

In the Southern Hemisphere, the orca types are more straightforward, and they are organized simply into Types A, B, C, and D. However, Type B orcas are further split into Type B (large) and Type B (small) orcas. Southern Hemisphere types also tend to have a brown or yellowish hue due to the diatoms on their skin.

Killer whale types. Illustration by Albino.orca.

Type A

Type A orcas are large, growing up to 31 feet (9.5 meters), and primarily feed on minke whales. They inhabit the open waters around the Southern Ocean, and follow their minke whale prey on their migration routes around Antarctic waters.

Type B (Large)

Type B orcas are also known as Pack Ice orcas because they forage for seals on pack ice. They are renowned for their unique hunting strategy, where they work together to create waves to wash seals off ice floes.

Killer whales create a wave to knock a seal into the water

Type B (Small)

The other Type B orcas are known as Gerlache orcas, which originates from the Gerlache Strait of the Antarctic Peninsula. The regular diet of these orcas is unknown, but they have been sighted around penguin colonies, where they occasionally feed upon penguins.

North Atlantic orcas off Lofoten, Norway. Photo by Rene.

Type C

Type C orcas are also known as Ross Sea orcas. At 20 feet (6 meters), they are the smallest of the southern hemisphere orcas, and they typically inhabit thick pack ice. They have been observed eating Antarctic toothfish; yet, whether or not they are primarily fish-eaters is currently unknown.

Type D

Type D orcas are also known as Subantarctic orcas. They are the rarest of the southern hemisphere orcas, and they have the smallest eyepatch of all the orca types, both Northern and Southern Hemisphere. Like the Type C orcas, they have been observed eating fish, such as the Patagonian toothfish, but their primary diet is unknown.

Other Orca Ecotypes

Orca near Auckland, New Zealand. Photo by Aucklandwhale.

Researchers are only beginning to understand orca ecotypes, and many of the ten types listed above are fairly recent discoveries. There is a great possibility that, in addition to classifying some of these types as new species, researchers will classify new orca types in other regions.

For example, in New Zealand, there is a resident group of orcas that consists of 117 identified individuals. These orcas are generalists, and while they primarily prey upon sharks and rays, they also prey upon fish, whales, and dolphins. This behavior does not line up with any of the five Southern Hemisphere ecotypes, so it is quite likely they will be classified in their own ecotype in the near future.

For more information about orcas and how you can help protect these magnificent wolves of the sea, please visit Whale and Dolphin Conservation and NOAA Fisheries.

2.1 Who are the orcas?

Task B

Mortality and Abundance Index for S. Resident Killer Whales and Chinook Salmon

What's Killing Killer Whales? How banned chemicals lingering in ocean waters are hurting orcas Scholastic Science News, March 4, 2019 , By Amy Barth

CORE QUESTION: Cite evidence from the text to explain why killer whales likely have higher levels of PCBs than any other animal.

Last September, a crowd gathered at a public hearing in Seattle, Washington, to discuss the plight of a local population of orcas known as the southern resident killer whales. Over the summer, three members of the group had died, including a newborn calf. Many people in attendoing enough to protect the animals.

For decades, the number of killer whales living off the coast of Seattle has been shrinking. Today, only 74 southern residents remain. A decrease in Chinook salmon, their main food source, has contributed to their

other. On top of these threats, orcas are dealing with another challenge: chemicals called polychlorinated biphenyls whale populations may not survive the next 100 years because of PCB pollution.

PCBs first came under scrutiny in the 1970s, when birds, seals, and otter populations began rapidly decreasing.

-up calls these chemicals might be hurting marin -Pierre Desforges, a biologist at Aarhus University in Denmark. He led the recent investigation into the impact of PCBs on orcas to learn what it might mean for their future.

DANGEROUS CHEMICALS

PCBs were once widely used in things like paints, plastics, and electrical equipment because the oily substances are resistant to extreme heat and pressure. The U.S. banned the chemicals in 1979 after they were found to be highly toxic to people and the environment. Other countries followed suit. But by then, the damage had already been done.

Decades of making products containing PCBs had allowed the chemicals to enter the air, water, and soil. Waste containing PCBs was dumped in landfills, where the chemicals leaked into groundwater and made their way to the ocean. In addition, PCBs had leached into the sea from paint used on ships. Much of this pollution remains

compounds from breaking down easily.

HARMING WHALES

Not only do PCBs stick around, they build up in

fat, which is abundant in marine mammals as blubber. The chemicals cling to fat in the milk of mother whales too, passing from mom to baby. And PCBs become more concentrated as larger animals

FIONA GOODALL/GETTY IMAGES INVESTIGATING A DEATH: Scientists collect tissue samples to measure pollutants in a dead orca in New Zealand.

eat smaller ones. As predators at the top of their food web, orcas have the highest measured PCB levels of any animal (see Trouble at the Top).

Desforges and a team of scientists set out to analyze the amount of PCBs in more than 350 orcas across 19 whale populations worldwide. The data came mainly from blubber samples previteam made a computer simulation that predicted how those PCB levels will affect the populations in years to come.

exposed animals. Tiny creatures called plankton take in the substances. Fish consume the plankton, and marine mammals eat the fish. The higher an animal is on the food web, the more concentrated its PCB levels become, a process called biomagnification.

PCB exposure takes a toll on killer w

off illnesses. PCBs also make it difficult for females to have healthy babies. No southern resident calf, for example, has survived since 2015.

simulations showed that 10 of the 19 studied populations will experience a significant downturn within the

[PCB] concentrations in killer whales were really high, but it was surprising to see how

HOPE FOR THE FUTURE

mammal conservation efforts in Seattle. She attended the hearings and understood the outpouring of emotion.

t a sick juvenile southern resident whale called J-50 before she died. NOAA had helped other orcas in the past, like a calf named Springer who became separated from her mother. Barre and other scientists cared for the calf until she was healthy enough to rejoin her family. Unlike Springer, though, J-50 was still with her mother. NOAA experts decided it was best for them to stay together and hope J-50 pulled through.

Although people were saddened by the death of J-50, there is good news for the southern residents: Several are

spot: Populations in remote areas where PCB levels are lower, including Norway and Antarctica, are growing.

Also, PCBs in the environment are decreasing as they gradually break down. But there are still a lot of old

KATE FRANCIS TROUBLE AT THE TOP

How Does Echolocation Work?

December 9, 2015

Survival instincts are mysterious in a mysterious world.

because of the special skills it requires to perform, but also because of the nature of the underwater kingdom in which its used.

understand, but underwater, the whales that use echolocation might as well be doing so on the moon.

into their environment and then listen to the echo in order to determine distance and identify unique features. Orcas have even been said to possess the ability to identify tiny objects such as pennies resting on the floor of the ocean. The acoustic nature of the water allows sound to travel huge distances and maintain its original clarity.

An ocean of music, indeed.

MAINTAINING SOCIAL ORDER

At the core of every orca pod is a detailed hierarchy. Families maintain close contact and are rarely to

keep track of pod-orcas.

Orcalabpopulation. Clicks, whistles and pulsed calls emitted by orca whales not only allow them to speak to eachother, they create a virtual map for each whale, locating reach member of the pod as though they were drawn out in front of them.

HUNTING

least close enough for one hunter to be alerted of its presence. That orca will in turn alert the rest of the group in order to organize an effective hunting procedure.

Echolocation allows orcas the ability to coordinate their hunting efforts in the absence of light or other recognizable features beneath the water. They can sense the movements of their prey as easily as we can see an animal on land from 20 yards away.

UNIQUE LANGUAGE

Orcas use pulsed calls as their primary form of communicationseparate clans of orcas are easily identified. Orcas living together

use similar calls in close proximity, so much so that orcas in captivity in close quarters with bottle-nosed dolphins have shown tendencies to , which includes far more whistles and clicks. This is a phenomenon known as vocal plasticity, and

HUMAN BEINGS & ECHOLOCATION

topic. Enter Daniel Kish, a man

Invisibilia as part of their pilot episode.

isolated to whales and bats.

ve been perfecting it for centuries, echolocation is just one more secret of the deep

Communication and Echolocation

Sound in the Sea

Sound waves travel through water at a speed of about 1.5 km/sec (0.9 mi/sec), which is 4.5 times as fast as sound traveling through air.

Killer whales probably rely on sound production and reception to navigate, communicate, and hunt in dark or murky waters. Under these conditions, sight is of little use.

Sound Production

Killer whales produce sounds for two overlapping functions: communicating and navigation (in the form of echolocation).

Killer whales produce whistles, echolocation clicks, pulsed calls, low-frequency pops, and jaw claps.

A killer whale makes sounds by moving air between nasal sacs in the blowhole region.

In contrast, a human makes sound by forcing air through the larynx. The vocal cords in the larynx vibrate as air flows across them, producing sounds. Our throat, tongue, mouth and lips shape these sounds into speech. The larynx of a killer whale does not have vocal cords.

A tissue complex in a toothed whale's nasal region, called the dorsal bursa, is the site of sound production. This complex includes "phonic lips" (sometimes called "monkey lips") structures that project into the nasal passage. Toothed whales make at least some sounds by forcing air through the nasal passage and past the phonic lips: the surrounding tissue vibrates, producing sound.

Releasing air isn't required for sound production. During some vocalizations, killer whales actually release air from the blowhole, but these bubble trails and clouds are probably a visual display.

Communication

Killer whales use whistles for close-range, or private, communication and coordination of behavioral interactions between animals. Whistles are high pitched, show a high degree of directionality and are highly modulated, as a result, they don't carry far underwater.

The frequency of killer whale whistles ranges from about 0.5 to 40 kHz, with peak energy at 6 to 12 kHz.

Studying northern resident killer whales, researchers found that the whales produced more whistles when they were close to other individuals and only sporadically emitted them when the whales were dispersed over larger areas.

Transient killer whales also use whistles, but more sparingly and have a smaller repertoire in comparison to residents.

Pulsed calls are the most common vocalization of killer whales.

Experts think these calls function in group recognition and coordination of behavior.

Killer whales make these calls at frequencies of about 0.5 to 25 kHz, with peak energy at 1 to 6 kHz.

Calls that sound the same time after time are called stereotyped calls. All a killer whale's stereotyped calls make up that whale's repertoire.

The individuals of any particular pod share the same repertoire of calls, a vocalization system called a dialect.

Although scientists have noted that there is some type of structure to the calls, a dialect is not the same thing as a language.

Analysis of killer whale call patterns has demonstrated substantial differences between the dialects of different pods.

o Pods that associate with one another may share certain calls. Pods that share calls are called a clan.

o Pods may share a certain level of their repertoire with other pods while other portions are unique. The more similarities they share may indicate the degree the pods and individuals are related.

o No two pods share the entire repertoire. Thus, each pod has its own unique dialect. In fact, the vocal repertoires of each pod remain distinct enough that scientists can identify pods by the sounds they make.

o Killer whales that are separated by great geographical distances have completely different dialects. An analysis of Icelandic and Norwegian killer whale pods revealed that the Icelandic population made 24 different calls and the Norwegian whales made 23 different calls, but the two populations did not share any of the same calls.

A calf is most likely to develop calls like those of its mother. Vocal development studies at SeaWorld have determined that a calf learns its repertoire of calls selectively from its mother, even when other killer whales may be present and vocalize more frequently than the mother.

A calf can vocalize within days of birth, but sound production is shaped with age. A calf's first vocalizations are "screams" loud, high-pitched calls that bear no resemblance to adult-type calls.

At about two months, a calf produces its first pulsed calls with similarities to adult-type calls.

Vocal behavior appears not to be genetically predetermined. Calves learn which calls to make and under what circumstances.

From two to six months, a calf's repertoire increases. Calves continue to learn calls until puberty.

Like many other animals, toothed whales may also communicate using a variety of postures and gestures. Some behaviors, such as head-butting and jaw-snapping, are usually assumed to communicate aggression. The purpose of other behaviors, including breaching and pec-slapping, is not clearly understood.

Echolocation

The term echolocation refers to an ability that odontocetes (and some other marine mammals and most bats) possess that enables them to locate and discriminate objects by projecting high-frequency sound waves and listening for echoes.

A killer whale echolocates by producing clicks and then receiving and interpreting the resulting echo.

The echolocating killer whale uses its phonic lips to produce directional, broadband clicks in rapid succession, called a train. Each click lasts less than one millisecond. One study of resident killer whales measured broadband, bimodal echolocation clicks that typically showed low frequency peaks between 20 to 30 kHz and high frequency peaks between 40 to 60 kHz.

The click trains pass through the melon (the rounded region of a killer whale's forehead), which consists of lipids (fats). The melon acts as an acoustical lens to focus these sound waves into a beam, which is projected forward into water in front of the whale.

The sound waves produced by a killer whale bounce off objects in the water, and their echoes return to the killer whale.

The major areas of sound reception are the fat-filled cavities of the lower jaw bones. Sounds are received and conducted through the lower jaw to the middle ear, inner ear, and then to hearing centers in the brain via the auditory nerve.

Killer whales often need to navigate in the absence of light/good visibility. Therefore, hearing is essential to them. The killer whale's primary sensory system is the auditory system. It is a highly-developed system that includes biological sonar ability or echolocation. Echolocation helps killer whales determine the size, shape, structure, composition, speed, and direction of an object.

Relationship to Feeding Habits

The use of echolocation and calls may vary greatly between fish-eating and mammal-eating populations of killer whales.

In the North Pacific, resident killer whales are more vocal and 27 times more likely to be producing click trains for echolocation. These differences are likely due to the fact that transients attempt to prey upon other types of marine mammals, which have more acute hearing in the frequency range of sonar clicks compared to fish. In an attempt to go unnoticed, studies suggest that transient killer whales use passive listening more to detect and locate marine mammal prey instead of relying on echolocation.