When I chose hermit crabs as my topic for this month, I wasn’t exactly sure what I would find. It turns out that hermit populations are generally in good shape at this moment [although the popularity of hermit crabs in the aquarium industry does warrant a little concern- because of the effort and expense needed […]
Archive for the ‘aquatic systems’ Tag
Not upwardly-mobile?
Any safe haven?
Over the past month, I’ve packed up my belongings and then unpacked them again as I moved between apartments. That got me thinking about animals that travel with their ‘house’, and so my topic for this month’s posts is hermit crabs. This is a topic that is pretty well unknown to me. During a […]
A safe port for harbor seals and other marine mammals
As I mentioned in my last few posts, harbor seals (and a wide variety of sea creatures) seem to challenged most by competition with humans (for food and space), pollution, and disease. Although several harbor seal populations appear stable or increasing, there is still concern about seals in Alaska, Scotland, and other locations. Given human […]
Disturbing the seas
In my last post, I explored the large issues facing harbor seals throughout the 20th century, including competition with humans, pollution, and disease. In looking at the last decade or so, these themes continue to be important but I think that they have become more indirect in nature in some cases. Although seals still eat […]
Harboring organochlorines
A quick look at harbor seal population trends around the world suggests that there have been ups, downs, and even some unknowns- catastrophic crashes in one part of the world while numbers grew in another and scientists couldn’t determine the pattern in a third. This wide-spread species shows corresponding variation in population status, but three […]
Life in cold water
As I write this, snow is falling outside on a cold, wintery New England day. Beautiful to look at and fun to play in when all bundled up, but it’s nice to know that I can come in from the cold at any time. I am amazed by mammals and birds that survive in environments […]
Connecting the dots
Over the past few weeks, I’ve been looking at the issue of habitat fragmentation in respect to how it divides populations and presents barriers to animal movement which can limit reproductive success and gene flow. When I started gathering information on how to combat and mitigate habitat fragmentation, most of the resources I came across […]
Trapped by the matrix
In my last post, I looked at the consequences of habitat fragmentation when we build roads or dams or other physical structures- we construct barriers that are useful to us, but not so helpful to the plant and animal populations we isolate. And sometimes we create obstacles to movement even when we think we’re making […]
Why didn’t the beetle cross the road?
As I have mentioned before, habitat fragmentation is one of the primary issues facing species around the world today- while it is far too big a topic to tackle in its entirety during one month’s posts, I think that investigating a few of its manifestations is manageable. I also think it’s necessary, since we have […]
Going on the offensive for sharks
Over the past few posts, hopefully you have gotten a sense of how a combination of increasing demand and general prejudice has led to massive overexploitation of shark populations around the world- some of the information I have passed along is pretty bleak. But I don’t want you to think that it’s all doom and […]