What is diversity and why is it important? Why do environmentalists carry on so about it?
A single species' population has many individuals that carry different genetic variations which may not be expressed by the population at large, but stored in the genetic code. Individuals that have the expressed code fitting the demands of new conditions can allow the group to survive difficult environmental stress.
Trophic hierarchies within niches of organisms have different specialists with redundant attributes. And if conditions, such as weather alterations, illnesses, loss of food sources, toxic conditions, cause extinction of some specialist species within a habitat, the environment can, to a degree, continue. However, the redundancies of the specialists, within the trophic layers, are vital to the plasticity and resiliency of the environment. Losses of specialists can cause trophic collapse reducing function and production of the environment. Generalist species can take the place, to some degree, the position of the specialist but may not fulfill all the attributes and functions to be the surrogate support the trophic layer and collapse may only be a bit later rather than sooner.
So, genetic variation allows populations to weather ecologic alterations. Redundancies of specialists within trophic layers allow for whole habitats to weather ecologic alterations. Wolves, spotted owls, polar bears are in one tropic layer but have few redundancies within their habitats. Their numbers are few so their genetic library is limited. With climate change how resilient is the world's environment to human consumption of species and habitats?
Monday, May 30, 2005
mountians-green
Saturday, May 28, 2005
the human interface
The question comes up, "why do humans create an ever exspanding world which suites only people?' The answer is, all organisms do and at all times. Weeds invade our perfect lawns. Argentine ants are over taking native Californian ant populations. House flies buzz over 13,000 feet of Mauna Kea, Hawaii. (http://www.ifa.hawaii.edu/mko/telescope_table.htm) Sometimes this exspansion is somewhat benign and many times it is not. Sometimes the exspansion can in a short time, geologically, change the entire world. (http://www.gps.caltech.edu/users/jkirschvink/)
Sunday, May 15, 2005
black trees
People's Pets, Pests and Parasites...
Mountains that ring Los Angeles burn so frequently that the trees do not have time to re-grow. Fire ecology means that the plants and animals have adapted to periodic conflagrations. However, even though the mountains are not developed, the cities and the ever-increasing human environment affect them, and so fire comes more frequently and has more devastating effects. (http://www.werc.usgs.gov/news/1999-09-16b.html ) What this means is that this undeveloped land is in effect, 'developed' and the plants and animals that live there are more inclined to be tolerant of disturbance and dependant on humans.
What kinds of plants and animals live with or near people and benefit from their proximity?
Mostly animals domesticated or habituated to take food and find protection from living near or with humans... and they bring all of their pests and parasites, too.
Zoonosis disease is like a bonus point for civilization and animal husbandry. Zoonosis is when viral and bacterial disease and all other parasitic diseases, which are not species specific but can jump easily from one animal to another. Pets, dependent on people for food shelter and reproduction... have transmitted Tuberculosis, Plague, Rabies, Ringworm, and Lyme disease. Domesticated food animals like pigs, live in crowded conditions near farmers and cities. Diseases like influenza viral strains, of say, the avian plus the human specific influenza viruses, (which have receptors and similar biochemistry within pigs) which can either kill one or the other, now, within the vessel of the pigs' systems, can do both. Even pet dogs can be infected and can carry potential diseases that may be passed onto their owners and trainers, which may have originated from some other animals across the globe. (http://www.recombinomics.com/News/05140503/H3N8_Florida_Widespread.html)
The pests of humanity like rats and mosquitoes have other interesting stories. Rats and mice that carry the Hantavirus come in contact with humans because of seasonal conditions. (http://coloherp.org/cb-news/archive/vet-med/hantavir.php) When rains increase the food supply for rodents in the Southwest, their populations expand, but drought brings them into cities where people sprinkle and store food. The rodents invade the peoples' homes and transfer the virus through their excrement either fresh or dry. Although, experts have said that Hantavirus is rare it has found a home in large cities like New York. (http://www.health.state.ny.us/nysdoh/communicable_diseases/en/hanta.htm)
People spray, scrape, dig, uproot, and pour concrete over the land. Near the confines of their cities, plant and animal life is different. Plants and animals must quickly take advantage of momentary peaks of water use or rain, crops or garbage, pets of prey or illness. What plants or animals existed where the people live, are gone or mostly and those at the perimeter of the cities are mostly gone, too.
Weeds - plants that take advantage of the disturbance caused by people - grow quickly, fruit and die. The insects at the interface of the human environment are mostly the groups that either eat what humans grow or throw out, or eat the detritus and carrion.
So, in the spring of 2005, affected by several years of drought and fire, the rains came. Forests protect the mountainside and the lower watersheds by holding back waters and rocks and mud. The forests of Los Angeles were mostly gone, burned, or so near completely burned, they looked like a landscape of black skeletons.
The Cement Rivers carried the majority of the water to the ocean. The Bolsa Chica may not survive another season of rain like this, especially if fires come in summer and burn what is left of the San Gabriel's.
Thursday, May 12, 2005
diatom cover
The Mugu marsh has many micro-habitats that support a variety of wetland life. Mugu marsh is also a Naval Base which scrutinizes all who enter. Only those with official business on the Base can step foot within the gates. This is a good thing for plants and animals that have been extirpated from their other wetlands, beaches, and salt pannes ...they have a small safe place for a while.....
People, no matter how thoughtful, impact these sensitive areas. Scientists who study the environment must tread lightly. SUV's and ORV's never ever - I repeat - never tread lightly. Tiger beetles live in sand in mud and eat the flies, ants, bees and other beetles that cross their holes in the soil. As adults, disturbed areas in the marsh, along beaches, sand bars, along rivers and streams, salt flats, run until they are torn up for buildings and roads. So many spots for tiger beetles, and the animals we support near water have been lost to the industry of people.
Wetlands were the trash bins of cities.
Now, the wide open areas are for off-roading.
Insects that live near or develop in water can carry disease, but most do not. The insecticides that kill the mosquiotes and black flies kill other insects as well. And,.... DDT still hides as a poison in the mud.
People's buildings, even miles away, impact the beaches and marshes because water flows downhill. People who spray lawn grower and pesticides might as well pour those chemicals directly on us! Everything that may be poured, excreted, spilled, leaked, regurgitated or purposely put on the streets ends here. Beaches and marshes are so full of the chemicals of people, the water in the mud can cause animals to be sick, be less fecund and die early deaths.
The marshland used to protect the oceans by filtering the water that flowed through the upper watershed, but there are more people pouring and spilling then there are natural filters to filter. Even if the people filter the water (supernatant) that flows from their streets from the urban sludge, people must find ways of disposing of the 'matter' safely. Increasingly, there are fewer places that can be used as dump sites that are at a distance from urban/suburbia. The Army Corps of Engineers have a special division that supervises the Department of Defense's dump sites (Formally Used Defense Sites - FUDS) but are concerned that urban development is growing faster then they can assess and maybe clean up. The sprawl will be at the edge of many areas set aside and made inaccessible because of radioactivity, explosives, and other toxic materials used for war.
.................I digress..........
This is a picture of Salicornia surrounded by diatom mats. Diatoms are silicon 'shelled' algae that will grow together on the soil when tides of the ocean fill the marsh and stands for a time. Tiger beetles can run across the slick of water to catch Ephidirdae feeding on the dyeing vegetation. The diatoms grow greenish, then turn yellow then black. Pink fungus grows with the diatoms in the mud. It may look radioactive, but it isn't.
Rattle snake at the marsh.
This rattle snake is a meter long. The ice plant planted to secure the mud from tidal forces, also provides caves and protection for her and her children. It is always a good thing to be careful walking in the iceplant (a non-native Californian plant). This snake was in the shade and looked like the wrack thrown up on the sand. The sun was setting and she was resting near her hiding place.
This snake has a lovely set of rattles. Not all adult snakes keep all of their rattles as they grow and so counting the 'buttons' is not a good way of aging the reptile.
There are rats and voles and mice for snakes to eat. Rats, voles, mice eat beetles! I like snakes.
Tuesday, May 10, 2005
Huntington Beach - Bolsa Chica.
The San Gabriel River used to be a part of the Bolsa Chica marsh. It still does to some extent, but so much of the water has been diverted and is used for the Valley's people. It flows in a cement channel and pours into large pools to recharge the aquifer for 1.5 million people. In the Bolsa Chica tigers ran. There are birds. there are lizards. there are insects of other orders. But, are there tigers? C.s.frosti like me?
Mugu morning
This is my home. I lived in the upper marsh where most of the mud is covered in Salicornia sp.. There are flies, Ephidridae, to eat. Formica to eat if they don't eat the larval tigers in their burrows. And waters flow in and up from the ocean and down from the upper watershed. In the early hours of the morning, sand pipers and the sparrows come to my panne to feed. Some tigers may not have dug a deep enough hole or found a place to hide in time before they froze in place from the cold 55 degree weather.
Birds with long beaks dig deep in the mud. They come in groups. When the sun rises, they fly. In the dark of the morning, cormorants bicker with each other for a steady spot on the high tension lines near by. Who said they could perch with their short legs and webbed feet?
When the tide rises the mud gurgles and burps.
Friday, May 06, 2005
Stripped forest.
Waters and boulders and trees and mud came crashing through this valley. The water was above the tree line. The trees bowed to the force of the torrents and their branches and leaves were stripped from the main trunk like weeds in a lawn mower. Most of the trees that were left this way were pulled out by their roots and became battering rams... others survived and have deep red wounds, looking somewhat like pipe cleaners
Mouth of the San Gabriel River after 2005 storm
Some places in the mountains rains came down to over 20 inches per day! Water not only over flowed the banks, but the filled valleys in the mountains, above the tree line, and ripping out large sections of the forest. Silly people who live at the mouth of the river heard the pounding of boulders as large as busses bound by hitting their bridge to the city bellow. No person who lived in the mountians died. The three dams above are still three months later filled with dead trees....
Thursday, May 05, 2005
San Gabriel River alder trees before winter storm.
Water flowing in the San Gabriel River come from rains of the past and from snows higher and farther away. Water slips through cracks in stones and through tiny grains of stone from deep within... jumping out at the sides of the hills... falling to the ground... darting here and then disappearing there.... Most years there is very little water. Plants have evolved to reach deep in the ground or come out of their seeds at wet times or after a summer fire or even a winter mud slide/flash flood. Alders, like willows need more water and so crowd the river's edge. Animals get water from where ever they can... some come down the mountains to the houses and pools... and streets.
This river flow is at the mid section of the mountain high above Pasadena, California.... At one time tiger beetles ran the river's mud banks. Are there any left?
Water in Death Valley - life in Death Valley!
In the spring of 2005, plants rose up from ground dry from a six year drought. Bugs rejoiced, ate, mated, with the hope this miracle would come again. Can you image what California looked like before the oceans lost water to the poles and the North American Continent rose just enough to let the seas pour out and the marshes ran dry. This is east of Los Angeles and Ventura (where I came from) - there must have been a string of islands filled with beaches and marshes of tiger beetles!
Tiger beetles actively digging burrow.
This is the salt panne where I came from. The plants around the edge of the open space is Disticulus spicata ... It somewhat appears to be like crab grass. It grows by runners. It never has tall blades. It grows along the edge of areas with salt water inundation occurs regularly and where the saline condition of the soil is extremely high. The water comes in and floods the basin, then evaporates until salt crystals form. Some crystals become sharp stilettos in the baked and dry mud and some become long strands of angle hair.
Disticulus is found along the California coastline where there are marshes which dry out now and then.... and, Disticulus grows in patches in Death Valley where there used to be ocean tides. Tiger beetles live there in the muds and sands of ancient ocean beaches.
This winter, the hundred year storms created lakes of water not seen for so long. Springs in the desert had pupfish mating, marsh plants - Disticulus and Salicornia sp. (pickleweed - edible for humans)- flourished, and tiger beetles ran.
In these holes larvae wait for small animals to walk by unaware of tiger beetle awaiting jaws. Adult tiger beetles dig holes under the plants and rocks for their night time refuge and rest. Solitary bees dig holes like these next to tiger beetles. Sometimes the bees become food for tigers. Tigers are maticulous about their appearance (they clean themselves all the time and when they are 'nervous') and their holes in the mud are dug in perfect cirlces - they are perfect!
Wednesday, May 04, 2005
C.t.sigmoidea larvae in the soil.
Cicindela trifasciata sigmoidea were never in large numbers when a survey was contucted of Mugu in 1982 by the Los Angeles County Natural History Museum. In 2003 very few - two to be exact - were found. They mated and this was one of their offspring. The larvae were robust and ate well. But because they were in captivity, and probably because their diet consisted of commercially grown fruit flies, they developed faster and went into pupation as smaller instars and were more prone to deformaties.
Within hours of shedding its outer skin, a transparent pupae emerges. Pigmentation begins the second day starting with the eyes, then the mandibles, then the legs and the elytra. Pupae, many times, lie under the soil in this configuration - on their backs.
Tuesday, May 03, 2005
Acres in Mugu lost in the storm.
Mugu had C. gabbi, C. hemorrhagica, C. hirticolis gravida, C. trifascaita sigmoidea, maybe some C. oregona (very few of them were here last year) living in the sandy beaches, the mudflats, and the drier salt pannes. C. gabbi was the most abundant especially in the mud flats. They are from San Diego south to Mexico. They are small, timid and beautiful.
This winter in 2005, the rains came and washed large areas of land away. There used to be many areas in Southern California where the tiger beetles ran, so if a terrible storm washed many of the colonies away there would be others to generate populations again. However, much of Southern California has cement and few open places where tigers can run.
C. senilis frosti face.
I and my kind (Cicindela senilis frosti) live in California. I was from a small salt panne in a salt marsh in Ventura county. We have three color types here in the marsh. Some of the other C.s.frosti are greenish, some are reddish and some are greyish. I am a bit reddish in some light and greyish in others.
You can tell my species from the more common C.oregona by the hairs (setae) on my head (and not just around my eyes) and from the tiny teeth near the end of my elytra near my butt(wing covers)! There is another colony of C. s.frosti, but they are in Riverside County California. Perhaps there are more. But chances are that they aren't. We need space, and insects, and good water. Heavy animals and such kill us when we are young in our holes in the mud.
Mugu Lagoon - acres gone in 2005 storm.
This is where I live. Well, I used to live. Most of my life I spent catching flies that would walk by my home in the mud. My parents died three years ago leaving me to dig a hole in the mud to hide from things that might eat me, to shade me from the sun, and to sleep until I emerged as an adult beetle. As a young beetle my wings needed stretching. I could tap them on my abdomen but flying left me upside down on the dirt.
The sun made me fast. Faster then the other insects around me. Every morning I would dig myself out of the dirt and stand in the sun. If it got too hot, I would run to the shade. I could feel the temperature rise and I would stand taller and taller away from the hot ground. If I kept my temperature up to 32 degrees C, I could out run the fastest fly, wasp, and spider. But, as night fell, I had to find a spot to hide from the night and morning birds. When I was cold, below 25 degrees C, I was food for all.
C. gabbi head drawing.
From a centimeter off the ground, the world is flat, the air is thick, water can be walked on. The sun makes your legs move faster, but at night, the cold freezes your joints to a stop. Food is everywhere and you will eat what ever your can. Anything can be subdued with sharp jaws.