Saturday, February 14, 2009

The Wild Animal Park
















At the Wild Animal Park 2009: Hornbill swallows mouse.

Wednesday, February 11, 2009

Coastal Sage: Going, going, gone.

McMansions to replace some of the remaining coastal open space in San Diego County.






Another mesa gone forever.
It was a great place to walk.

Monday, September 29, 2008

Changing seasons

This pic is from the same spot throughout 2007-2008. You can see the winter rains bring green life to the coastal sage plant community. Soon the heat of summer returns bringing with it death and destruction...or whatever.

Native Harvester ants







Harvester ants were abundant along the coast but have largely been displaced by the invasive Argentine ant. Pogonomyrmex subnitidus still occur in Torrey Pines State Park in San Diego along the coast. These ants collect seeds (hence the name) and the picture above left shows a nest. Scattered all about the nest are seed husks (right pic-nest hole in center) and abandoned refuse the ants carry from the interior to the surface. The pic below shows a pogo being attacked by another California native Dorymyrmex insanus (the small black ant). The pogo has a seed in its mandables and the dory is trying to steal it or is just raising hell. These ants primarily eat seeds yet apparently like most animals they appear to be opportunists. The following video shows a harvester ant attacking a moth larvae during a moth outbreak. During the spring of 2008, these moth larvae could be found everywhere crawling all over the ground and eating vegetation. This moth outbreak was followed by a carnivorous Carabid beetle outbreak refer ed to as a numerical response. The abundance of these caterpillars was a great source of food for many carnivorous insects.



Messor pergandei is another harvester ant found in the deserts. The following video is of a foraging trail in the Anzo Borrego Desert. At a certain point in time, the signal is given to launch a "seed run" (like a beer run..) along "trunk trails" where the ants pour out of the nest and head off in a column like an army on the move. They soon reached their destination and spread out -every ant for herself! With plunder in mandible, they soon return to the nest. It was striking to see this large column of onyx ants cross the trail that just 10 minutes earlier was quiet and abandoned.

Harvester ants lend themselves to a classic experiment. Optimal foraging theory predicts that an animal will maximize energy gain per unit time when foraging. You can test this easily. If you find a nest, you can place seeds (or oatmeal) of varying sizes at different intervals from the nest.







I was assaulted by a fly in the above clip.



Wikipedia : Messor is a myrmicine genus of ants with more than 100 species, all of which are harvester ants; the generic name comes from the Roman god of crops and harvest, Messor. The subterranean colonies tend to be found in open fields and near roadsides, openings are directly to the surface. The Vessomessor genus was recently added to messor adding 8 more species.
Colonies can achieve huge sizes and are notable for their intricately designed
granaries in which seeds are stored in dry conditions, preventing germination. The structure of Messor spp. nests is complex and the genus on the whole is one of very accomplished architects.
Messor spp. are polymorphic and have a distinct caste of macrocephalic
dinoergates [big headed workers] whose role is of carrying and cutting the large seeds which comprise much of the colonies' subsistence.
Equipped with a tough shining cuticle, Messor spp. are slow moving and form long, seed-carrying runs. Colonies tend to be monogynous and are founded by a single queen alone







Saturday, September 27, 2008

Exploitation






Nectar is provided by flowers to help facilitate the dispersal of pollen by attracting pollenators. Insects and Angiospersms (flowering plants) have a shared evolutionary history and have coevolved with each other. Here we see an ant (Myrmecocystus sp.) drinking the nectar of Isomeris "bladder bulb". The plant is losing out as ants are notoriously poor pollenators. This is an example of exploitation found in nature.

The Purple flower is a species of Mallow being exploited by Formica moki, an ant found in San Diego County. Below is the intended recipient of the nectar fast asleep after a long night out!

Friday, September 26, 2008

Ants recruit to San Diego Barrel Cactus EFNs


The San Diego Barrel Cactus is found from N. Baja California, Mexico to the edge of San Diego County primarily along the coast in Coastal Sage scrub. This barrel cactus maintains extra-floral nectaries (EFNs - nectaries outside of the flower; floral nectaries attract pollenators in pollenation mutualisms). EFNs on the barrel cactus are modified spines that secrete carbohydrates. EFNs attract ants to protect the cactus from harmful herbivores (bugs). EFNs are found on a variety of plants not just cacti.
The following videos are of different ant species that occur on the cactus and presumably protect the cactus in exchange for a carbohydrate reward offered by the EFNs:





As you can see, these ants vary in their ability to protect the cactus. The larger Camponotus sp. does not recruit to food sources (apparently) as readily as Tapinoma sessile.

Defensive mutualisms 1


Defensive mutualisms are common in nature and are readily found in ant-plant associations. Typically these associations involve the plant offering the ants food directly (carbohydrate exudates) in exchange for protective services. These relationships are constantly evolving and should be thought of as "mutual exploitation" rather than casual friendly relations. Plants will skip out on offering valued resources if there was no benefit and vice-versa.

Sometimes, other insects (Hemipterans) harm the plant by sucking plant phloem but excrete honeydew which attract ants. Renowned biologist Janzen (1979) proposed that plants that haven't yet evolved carb. exudates directly to offer ants, will tolerate these harmful bugs as they attract ants that scare away much more damaging insect herbivores. Janzen proposed the maintenance of the herds of scale insects and other honeydew exuding homoptera is more or less a fixed cost for the plant, the equivalent of maintaining secondary defensive compounds and alkaloids (think of poison oak). The ants protect the trees from herbivores, vines, and mammalian browsers. A removal experiment supported as much. Below is a video of a native ant Tapinoma sessile interacting with aphids. Visible in the movie are aphid "mummies" or aphids that have been destroyed by parasitoids (insects that live inside the host and eventually kill the host - like in that movie Alien). The parasitoid was most likely a wasp that had oviposited its egg into the living aphid. The mature wasp emerged and left behind the hollow mummy.

Tuesday, August 26, 2008

More snakes: Striped Racer, Gopher

The Striped Racer Masticophis lateralis lateralis is HARMLESS to humans but there is no way you could catch one! You can sneak up on these guys hiding in the bush but with the flash they will dart into the chaparral and never be seen again.

They are one of the most common snakes in San Diego County. I am working on getting a video of these little bastards.

CALIFORNIAHERPS.COM writes:

Appearance
A fast-moving snake with a long thin body and tail, a broad elongated head, large eyes, a slender neck, and smooth scales. Dark brown to black with a pale yellow or cream solid stripe on each side which extends from the back of the eye to or beyond the vent. The stripes are relatively narrow - "2 half-scale rows wide."(Stebbins) The underside is cream or pale yellow tapering to pink toward the tail.
Behavior
Dirunal, often seen actively foraging in the daytime with head and forward part of the body held up off the ground searching for prey with its acute vision. Climbs vegetation and seeks shelter in burrows, rocks, or woody debris. Very fast-moving and alert, quickly fleeing when threatened, this snake is difficult to get close to. Like most Masticophis this snake will strike repeatedly and bite viciously when threatened or handled.
Diet
Eats lizards, small rodents, small birds, frogs, salamanders, small snakes. Juveniles will consume large insects.-


The San Diego Gopher Snake Pituophis catenifer annectens is also HARMLESS to humans but will scare the hell out of you anyway! I have a video of one but since we know it is just like little bunny froo froo I decided not to upload it. Pic courtesy of californiaherps.com:


CALIFORNIAHERPS.COM writes:

Appearance
A large snake with heavily keeled scales, a narrow head that is slightly wider than the neck, and a protruding rostral scale on the tip of the snout. Ground color is tan, light brown or yellowish, with large brown or blackish blotches along the back and smaller markings on the sides. The dorsal blotches can fuse together producing a very dark color. The underside is cream to yellow with dark spots. The back of the neck is often a dull orange.
Behavior
Active in the daytime, and at night in hot weather, and especially at dusk and dawn. One of the most commonly seen snakes on roads and trails, especially in the spring when males are actively seeking a mate, and in the fall when hatchlings emerge. A good burrower, climber, and swimmer. A powerful constrictor; kills prey by suffocating them in body coils or by pressing the animal against the walls of their underground burrows. When threatened, a gophersnake willl sometimes inflate its body, flatten its head and produce a loud hiss, often while moving its tail back and forth quickly which may sound like a rattle if this is done in dry vegetation.

Diet
Small mammals, especially pocket gophers, birds and their eggs, and occasionally lizards and insects.

Rattlesnake encounter blah blah blah...


May 13 2007. Rattlesnake again crosses my path. I wave it off and go seek shelter under a mulberry bush. This snake was actually at Torrey Pines State Reserve.






Another snake is seen at The Knoll just south of the reserve (see video below).




The Scripps Coastal Reserve a.k.a. "The Knoll" or "The Cliffs"


If your square e.g. old, you say

"Hello kind sir. May I have the privilege
of accompanying you on your afternoon stroll
down to the Knoll?"

and if your down you say:

"Hay baby wha's crak'n'?
Wanna go chill down at The Cliffs?"




just noted which version I use. Darn.

Rattlesnake encounter II Crotalus sp.

Yes another encounter with my old friend.
This time he looked well fed. They seem to be most active along the coast primarily in the spring. I took this photo in March 2007.

Rattlesnake encounter I Crotalus sp.

Back in June o' 07 oh, (june-oh-ohseven0) I was strolling along contemplating abstract things like how many eggs you could fit into your mouth without breaking them when I came upon this little fellow. His beady little eye struck me as odd so I had to get closer to see if it was elliptical or not as mentioned in the sdnhm.org herpetology web page.SDNHM.ORG WRITES:
How do I recognize a rattlesnake?
The main features of rattlesnakes include:
a broad, triangular head on a narrow neck ,
CHECK...
folding fangs , CHECK...
cat's-eye or elliptical pupils instead of round ones , LET ME SEE....
usually a rattle at the end of the tail (though this may be missing or broken) CHECK...
As you can see, picking out most of these characteristics requires being close to the snake. This is why we suggest that you leave any strange snake alone.
http://www.sdnhm.org/research/herpetology/resources4b.html

-oops! I didn't read that last part.

Western Blind Snake

In July, we found a blind snake (with vestigial eyes) roaming around on the ground at night. They live mainly underground and seek out ant colonies to eat. It had never been found before in the nature reserve. You can see a Crematogaster californica nest nearby that it quickly slithered down once we were done molesting it. Its scales were shiny silver like armor plating. The ants would attack but could not penetrate the scales! Magnificent! They are suprisingly small....see video below.













The following information is provided courtesy of digital-desert.com


Family: Leptotyphlopidae Order: Squamata Class: Reptilia DISTRIBUTION, ABUNDANCE, AND SEASONALITY
The western blind snake is widely distributed in southern California from the coast to the eastern border at elevations up to 1515 m (5000 ft). It seldom occurs in strictly sandy areas, alluvial flats or dry lakes. Little is known about abundance. A wide variety of habitats at lower elevations is occupied where conditions are suitable for burrowing, or hiding under surface objects and in crevices (Klauber 1940, Brattstrom 1953, Brattstrom and Schwenkmeyer 1951, Stebbins 1954, 1972). SPECIFIC HABITAT REQUIREMENTS Feeding: This snake eats ants, termites, their eggs, larvae and other soft-bodied insects (Stebbins 1954). Cover: This snake burrows, spending most of its time underground. It has also been taken under objects such as logs, rocks and among the roots of shrubs. They have also been taken under granite flakes (Stebbins 1954). Reproduction: No data. Water: The western blind snake seems to prefer moister habitats but is found in very arid environments, so permanent water is probably not required (Stebbins 1954). Pattern: This species prefers moist areas. In canyons, stony and sandy deserts, rocky slopes and boulder piles, and scrub. SPECIES LIFE HISTORY Activity Patterns: This snake appears on the surface at night but may be active underground at other times. Greatest seasonal activity occurs from April to August (Stebbins 1954). Seasonal Movements/Migration: No data. Home Range: No data. Territory: No data. Reproduction: Little is known about reproduction. An average of 4 eggs (range 2-6) is laid in late summer (Klauber 1940, Stebbins 1954). Niche: There is one record of this snake preyed upon by a coyote (Stebbins 1954). It is probably eaten by most avian and mammalian predators when encountered. Nothing is available about diseases parasites or competitors.

That night we ran into Camponotus dumetorium one of the largest California native ant species. You can see the size of a single soldier in the mans hand. They come out at night to forage for food etc.