Basic RadioCam Computer Lab Activity

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When Are Elephant Seal Pups Found At Año Nuevo? This inquiry is designed to demonstrate the seasonality of Elephant Seal reproduction and to familiarize students with the rookery image archive. The archive is housed at CSUMB and is available on-line. It contains more than two years of 10-minute-interval images from an Elephant Seal rookery in Central California. Students will: Propose hypotheses addressing optimal pupping season. Collect timestamped images with and without pups. Assemble data from entire class into a reproductive calendar. Revise hypotheses based on data and propose further research. Timing Depending on the extensions you choose this activity can be done in 30-60 minutes. Materials A computer lab with access to the internet is required. The computers should contain a browser such as Netscape, and if you are doing the extensions you will need a word processor and a simple paint program. A printer that can print graphics is also preferable for the extensions... color printing is not required, but nice. Summary Students collect one image from archive that has pups visible and another image that doesn't. They save those two images into a brief lab report. Using an overhead and a transparency marker, the teacher assembles the class data by tallying results onto a calendar. This works best when teaching more than one class, as the resolution of the calendar improves with more data. Introduction The basic activity we conduct to get students using the image archive is to answer the question, "When do northern elephant seals give birth to their young?" Answering that question may require that the teacher understand how to navigate the archive (although the kids can usually "teach the teacher" how that is done after a few minutes!). But most importantly it requires that the teacher be able to distinguish pups from other seals in the radio-transmitted JPEGS. A lead-in activity can be to have students make written predictions with a rationale for when pups are born. Pose the question, "If you were a mother seal, when would you want your pup to be born and why?" Have them turn in their sentences and then begin the exercise to see if their prediction is correct. Typically, a student with anthropomorphic tendencies will write a prediction like this: If I were a mother elephant seal I would have my pup in the summer when it is nice and warm. A student with experience in temperate terrestrial biology might write: If I were a mother elephant seal I would have my pup in the spring so it would have plenty of time to get big and fat for the winter. It is good that they are providing reasonable rationales, but by doing this activity they will discover when northern elephant seals actually have their pups. It is different from the other seals along the eastern Pacific coast of North America. Why  they have them when they do is open for scientific discussion... see discussion at end of this lesson plan. AND REMEMBER, seals don't really "choose" when to have their pups. The pups who are born at a particular time of year either survive or don't, keeping those genes in the population or removing them from the population. Lots of things can select for or against being born at a particular time of year. Generally it is related to food supply but also such things as the availability of mates for the females after weaning. Many people wonder why the elephant seals have such helpless pups during midwinter when storms, high tides and surf cause such a high mortality? Rookeries like the one being recorded by the radio camera are especially vulnerable. Doing the Activity When the students have settled in the computer lab have them open Netscape Navigator or Internet Explorer. If the lab is frequently used by other classes and students it is usually worth the effort to have the students RESTART their machines before opening the browser. Have them enter and bookmark the following web address into their location bar:     science.csumb.edu And then have them click on "Elephant Seal Project." The next stop is the Radio Cam button... The RadioCam page is fairly busy but one of the links is titled, "IMAGE ARCHIVE" and the students should click on that. They may get a bit sidetracked here since there is a live image posted to that page during daylight hours Pacific Coast Time. After a few moments repeat the instructions to open the link to the IMAGE ARCHIVE. The IMAGE ARCHIVE is simply a huge list of directories, labelled by date, each containing about 50-60 images. The time and date-stamped images are transmitted by radio from the remote site every ten minutes and loaded onto our server... so at the time of this writing there are over 40,000 images in our archive. Be patient when allowing the archive to load, as there are over 700 lines on that first page. When a student finds a image with a pup visible, have them right-click the image (PC) or hold the mouse key down (Mac) until they get the option to "Save Image As" or "Download Image." Save the image as "pup.jpg" onto the hard drive or desktop. Now ask the students to find and save an image without a pup visible. Save that second image as "nopup.jpg" onto the hard drive or desktop. After confirming that students have actually downloaded images containing pups you can go on to the class data collection stage of the activity OR you may want to continue with these more formal and tech-infused extensions. In practice the extensions are good, if time permits, because the students are forced to look closely at the images they have selected and may end up returning to the archive to choose superior photos. GO TO CLASS DATA COLLECTION STEP, OR CONTINUE WITH THE photo mark-up EXTENSION In this first extension the students close the browser (Netscape or IE) and open a simple paint program or photo editor. The goal at this point is to have students paint plainly visible arrows (yellow) pointing at the pups in the one image they have that contains the pups. At this point students are usually comparing images and deciding whether theirs really contains pups or not. About 1 in 10 students will have selected an image that only contains juveniles or weaners... not really pups. Pups are pretty easily defined for the students purposes as "the small black seals obviously nursing or next to a larger female seal." HERE ARE THE INSTRUCTIONS FOR USING Microsoft Paint. Do not double-click on the file to open it! Instead, open Microsoft Paint, select FILE-->OPEN, and select your JPEG from the desktop. The goal is to add arrows to each of the pups and make the images 400 pixels across. To draw the arrows, follow the instructions below: The images the students will be working with in the lab will of course be significantly larger! Often you can get away with drawing one or two arrows and then copying and pasting them to the other pups. To do this you have to learn to use the lasso tool (see below). After you have finished adding the arrows to each of the pups visible on the image, select FILE-->SAVE AS and save a copy called puparrow.jpg to your desktop. Remember to keep the file in JPEG format which most Photo Editors and Paint programs such as Microsoft Paint now do (since 1998). GO TO CLASS DATA COLLECTION STEP, OR CONTINUE WITH THE "RESIZING" EXTENSION If the students are using Microsoft Paint, close the file and open it in Microsoft Photo Editor. Choose IMAGE-->RESIZE -->SET TO PIXELS -->WIDTH = 400 pixels When the two images have been resized down to 400 pixels (@72 dpi) save them to the desktop. CONTINUE WITH PUTTING TOGETHER THEIR DATA SHEET... The students can then close the paint program or photo editor and open Microsoft WORD or WordPad or some other word processor. Have them insert the two images into a document with a title and captions. The captions should read, "In this image from DATE there were no pups visible at the rookery." "In this image from DATE there were X pups visible at the rookery." Depending upon the computer literacy of the students, they can also use a text editor or HTML editor and create their own web pages. CLASS DATA COLLECTION STEP At this point you will want to return have the students return to the classroom or at least turn off the computers. On an overhead projector transparency, write down the two data points from each student. Use the same transparancy all day so that you get more and more data on the same sheet. If you want to distinguish between your classes, just use a different colored marker. The transparency should look something like this, but can vary depending upon how many data points you can collect (If you are teaching five periods of biology you will have some serious data!!!). Images with Pups   Images without Pups     June       July       August       September       October       November       December       January       February       March       April       May   The pattern that generally emerges from the data is for there to be pups apparent in images from January, February and March, and for images without pups to be scattered throughout the year. Occasionally, immediately after a storm, there will be Jan/Feb/Mar images without pups, but they are the exception. Don't discount that data. With enough students (usually more than 15) the trend will be obvious. At this point there are several directions you can take the students. One suggestion is to go now to the reproduction and survival module. Another is to reiterate this exercise by collecting data on when there are images containing large males or when there are images containing no seals. This can also be expanded upon by breaking the class up and assigning each student a two-week period or each two or three students a month (and a year!) where they go and count the number of seals they can see in an image from each day. This can then be summed up entered as a bar chart representing the population at that rookery during each of the 52 weeks in the year. A third is to briefly go over the life histories of the Northern Fur Seal(June), Steller Sea Lion(May-Jul), California Sea Lion(Jun-Jul), Harbor Seal(Mar-Apr), Guadalupe Fur Seal(Jun-Aug), with specific reference to their pupping seasons. Then return in greater detail to the life history of the northern elephant seal (at least what we know of it!). The question of why these seals have their pups during the months of January through March can be raised and discussed again. The students made predictions (hypotheses) and then made observations. The data from the observations was collected and a story emerged that either contradicted or reinforced the hypotheses. The students may come up with refined hypotheses and wish to collect more data. Explanations may be proposed for why the seals pup when they do, and those explanations (hypotheses) can then be tested... Either by going to published literature and data, or by designing experiments that can test those hypotheses, or by collecting more observational data. One explanation for the time of year that elephant seals have their pups involves the annual spring upwelling events along the Pacific Coast of North America. These events happen in most years and bring cold nutrient-laden waters from the deep ocean up along the coast into the photic zone. The subsequent bloom of plankton leads to an upsurge in the abundance of small crustaceans, squid and fish, including slower moving species that can be caught by the relatively incompetent and "unsupervised" elephant seal pups. Because the elephant seal mothers have invested a huge proportion of their body weight in the young weaners, they must hasten back to the rich feeding grounds of the North Pacific thousands of miles away. So instead of investing parental care in their offspring, they have invested parental calories. The model is that only during the rich fishing months of April and May are there enough slow moving species in shallow waters for the young weaners to learn to dive and capture prey. An entirely different explanation relates to the near extinction due to hunting of these seals, and the severe bottleneck their population has traversed. Old whaling and sealing texts such as that by Charles M. Scammon, describe more variation in pupping season, including the following statement: "Our observations on the Sea Elephants of California go to show that they have been found in much larger numbers from February to June than during other months of the year; but more or less were at all times found on shore upon their favorite beaches..." he continues "we have noticed young pups with their mothers at quite the opposite months." and he continues... "among a herd of the largest of those fully matured (at Santa Barbara Island, in June, 1852), we found several cows and their young, the latter apparently but a few days old." CSUMB Elephant Seal Project