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Citizens of the Sea: Wondrous Creatures From the Census of Marine Life

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National Geographic underwater photographers and the Census of Marine Life capture the astonishing diversity and the most intriguing organisms in the ocean in this riveting book, by marine scientist Nancy Knowlton. 

As you read lively vignettes about sea creatures’ names, defenses, migration, mating habits, and more, you’ll be amazed at wonders like . . .

· The almost inconceivable number of creatures in the marine world. From the bounty of microbes in one drop of seawater, we can calculate that there are more individuals in the oceans than stars in the universe.
· The sophisticated sensory abilities that help these animals survive. For many, the standard five senses are just not enough.
· The incredible distances that seabirds and other species cover. Some will feed in both Arctic and Antarctic waters within a single year.
· The odd relationships common in the marine world. From a dental hygienist for fish to a walrus’s one-night stand, you’ll find beauty, practicality, and plenty of eccentricity in sea-life socialization.

Brilliantly photographed and written in an easygoing style, Citizens of the Sea will inform and enchant you with close-up documentation of the fascinating facts of life in the ocean realm.

216 pages, Hardcover

First published September 14, 2010

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149 people want to read

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Nancy Knowlton

7 books4 followers

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5 stars
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44 (28%)
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21 (13%)
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Displaying 1 - 23 of 23 reviews
Profile Image for Riju Ganguly.
Author 37 books1,866 followers
July 9, 2023
This book had been bought for my daughter. But as I discovered over past few days, it’s for all ages and everybody. It’s about the creatures who live in those parts of the world that has made ours a blue planet.
The Sea!
And what a beautiful, mysterious, dangerous and fascinating world it is.
The photographs are awesome. Brief information provided alongside are thoughtful, succinct, and lucid.
The dimensions of the book also give it the feel of an album, making it friendlier.
Highly recommended.
Profile Image for Serena.
62 reviews
April 10, 2023
LOVED IT!! It was very interesting. I only had to renew it three times in order to finish bc I read 10 pages each night BUT IT IS DONE!!!
Profile Image for Vishy.
808 reviews287 followers
September 29, 2019
When I read 'The Universe Below' by William J. Broad, earlier this month, I fell in love with oceanography and marine life and went and got a few more books on these topics. 'Citizens of the Sea' by Nancy Knowlton was one of them.

'Citizens of the Sea' is based on the ten year Census of Marine Life research project which was a collaborative effort by scientists from across the world. The aim of the project was to study marine life in the ocean in different parts of the world, classify and document unique marine species, identify new species, attempt to take a census of marine life, and identify the challenges that marine animals face. Nancy Knowlton has used this research as the basis for this book.

The book is divided into many interesting sections. Each section in the book is focused on a particular theme. There are sections on how marine animals are discovered, identified and named, how appearances are important for them and how these evolved across time, how marine animals travel across the ocean, how they make friends and fight with enemies, how they find their partners, mate and raise their young ones, how humans are threatening their way of life now – these and other fascinating topics are explored in each section. As the book is published by National Geographic, the book is filled with stunning photographs in every page. They are so amazing and an absolute pleasure to look at. Many of my favourites were featured in the book – I was so happy to see the Coelacanth, which was thought extinct millions of years ago before it was rediscovered again, the Orange Roughy, which lives till the great age of 125 years and which was featured in a chapter aptly titled 'Methuselahs of the Deep', and the Fugu fish, which is famous in Japan. There were many amazing facts which were mentioned in the book. One of my favourites was about fishes like the blue-headed wrasse, anemone fish and the hamlet, which change their gender when it suits them, sometimes while mating, sometimes during parenting. I smiled when I read this sentence – "Paternity tests sometimes reveal that a father has become a mother" :) There are many amazing facts like this on every page.


I loved 'Citizens of the Sea'. It is a beautiful book filled with amazing facts and stunning photographs. It is a must read if you are an ocean / marine life enthusiast.

Have you read 'Citizens of the Sea'? What do you think about it?
Profile Image for g-na.
400 reviews9 followers
April 14, 2012
I was so disappointed in this book I only got a handful of pages into it before I put it away. The text itself is fairly juvenile, written for people who have little knowledge of the sea or its inhabitants. But that's fine, there's a place for books like that even if they don't appeal to me. What really frustrated me was the poor quality of the photographs. For a book that has about 50% of its pages covered with photographs you'd expect those photos to be of high-quality, particularly when the book was published by National Geographic. But the photos herein do not live up to the spectacular image quality we've all come to expect from National Geographic; some aren't even in focus. It's a shame they published it.
12 reviews
March 11, 2021
This is a good book for everyone who has no extensive knowledge of marine animals yet and wants to change that. There are lots of colorful pictures and short, informative texts included, that give you interesting insights into the world below the ocean's surface.
Unfortunately, I personally have been reading about these things from a very young age, and this book did not hold any new information for me. in fact, I found the texts very superficial, and would have wished them to go on a bit longer and elaborate on many of the interesting points they mentioned, then dropped. It was a bit of a frustrating reading experience. Also, many of the pictures were not of a very good quality, some were grainy or out of focus. This is unusual especially for a National Geographic production, and unfortunately made me substract a point from my rating.

I recommend this book to everyone who is curious about marine life, but doesn't know where to start first. It gives a good overview over many ecosystems and species of plants and animals, as well as their different habits, and does a decent job of explaining elementary facts, peppered generously with funny and/or strange tidbits.
Also, maybe buy it in your motherlanguage: since it is a US-american published book, it does not use the metric system or the Celsius scale, and had me confused and left with no real idea of how big, hot, cold or far away the things described in it were several times.
Profile Image for Micheala.
140 reviews13 followers
June 4, 2019
It was a good introductory level entry into marine life. The target audience (imo) is the average person who is slightly interested in learning about the vast range of oceanic life.

I personally didn't learn anything new, so I would say that if you've gone into biology (either as an undergrad or as a pre-established interest in nonfiction reading) you likely won't walk away with any new information. However that being said, I enjoyed my couple of hours of reading and the photographs are stunning.
13 reviews
July 1, 2024
This book was gifted to me by a friend a few years ago & I have finally finished reading it, which shows that you need to be a very dedicated person to read it in one sitting. Overall, it was still a great book with the most amazing facts and I would highly recommend this book to any ocean-lover or aspiring (or already) marine biologist.
13 reviews
Read
June 9, 2020
A truly fantastic book with amazing images and pictures of varying marine life. Information in the book was accurate and written in a way that was easily understood. I would highly recommend this book to anyone interested in the oceans and the marine organisms that live in our oceans.
126 reviews1 follower
March 8, 2021
Having enjoyed many years of scuba diving in the open seas, this book was irresistible. The diversity of the marine world is superbly captured with brilliant photography and detailed documentation. Our underwater world is truly otherworldly. The book enchants, amazes and delights.
Profile Image for Ashley Robichaud.
62 reviews
April 27, 2024
Solid introduction to ocean creatures, beautiful photography, maybe a nice start if you’re generally interested in the ocean, easy read
Profile Image for Danielle T.
1,294 reviews14 followers
August 17, 2013
I really wanted to like this book, but the prose killed it. The Census of Marine Life is one of the most astounding scientific undertakings in recent history, yielding many new species, behaviors, and revealing how little we actually know (in other words, directions for future researchers to start digging :P) There's a lot of cool stuff you can mention from the last ten years.

The only problem I have is that it's written for a *very* general audience. I do understand that a large part of the Smithsonian's job is scientific outreach, but with short (less than a newspaper article)'s paragraphs on a subject and phrases such as "Anemonefish like Nemo will...", it almost feels like the audience is expected to be either a child or have merely a passing interest in the subjects. Hook them with something general, sure, but take the opportunity to present more information!

The pictures were great, but as always you can find larger and higher resolution images online (and in some cases, video- like the octopus that seemingly appears out of nowhere from a rock which can be seen here). Might be good for a budding marine biologist or to pique someone's interest in the sea.
Profile Image for Ken.
173 reviews7 followers
July 13, 2015
My congratulations go out to the previous reviewers who damned the book after admitting not really reading much of it. Attention spans are apparently overated when it comes to objectively reviewing anything.
Sincere congratulations go out to the author and editors of this eye-catching gem in view of the fact that the dictum here was to take 10 solid years of research material (much of it dry and statistical) by multitudes of researchers with different backgrounds and interests in an extremely technical area and somehow prepare it for the average reader all in around 200 pages.
Sorry, but I read the whole book. I was never bored. I appreciated the photographs and artistic layout. Sometmes I felt the writing was a bit technical or obtuse.
If you are still reading this "review" then I recommend the book to you. You apparently have an attention span.
Profile Image for Paper Clippers.
584 reviews2 followers
Read
October 30, 2015
The astonishing diversity of ocean life will wow you in this riveting book, perfect for all ages, by marine scientist Nancy Knowlton. Citizens of the Sea reveals the most intriguing organisms in the ocean, captured in action by skilled underwater photographers from National Geographic and the Census of Marine Life.

The above is the summary provided by Goodreads.
Profile Image for Whit Preston.
27 reviews
June 22, 2013
Although I have only barely cracked the surface of this book, I am fascinated by the information contained within this volume. Like a great National Geographic documentary, there are numerous exotic creatures and spectacular photographs.
Profile Image for Kate.
30 reviews28 followers
March 24, 2013
i got half way through it, i liked it at first but then it bored me.
290 reviews3 followers
April 29, 2016
Some photos are really fascinating and haven't been seen before, nice job!
Displaying 1 - 23 of 23 reviews

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