Tuesday, August 30, 2022

An Encounter with a Giant Golden Orb Weaver Spider in Mt. Makiling, Los Banos, Laguna

Large body size, long legs, dark and bright markings describes Nephila pilipes

Large spider, large intricate web

A large female N. pilipes revealing its underside

To showcase the relative size of this giant spider 
 
Holding on to the golden silken threads of its web as it awaits its prey

The distinct double bright yellow streak on the abdomen

Releasing silken thread from its spinnerets 

Front view of its spinneret

Detail of markings on the abdomen and spinneret

As I approach its web, it began to vigorously shake it

The giant golden orb weaver 

It was during our early morning hike at the trail of Mt. Makiling in Los Banos, Laguna, that my daughter, Odette spotted this awesome giant golden orb weaver. Located just on the side of the hiking path, it has strategically laid out its large silken web across the shrubs and tree branches. The large female spider was in the middle of the web, patiently waiting to snare potential prey. As I was getting closer to the web, the lady spider began to shake her web vigorously, trying to distract me as she moves away. I was not distracted, I was more attracted to observe this lady giant spider!

GIANT GOLDEN ORB WEAVER, Nephila pilipes (ARANEAE: ARANEIDAE)

The giant golden orb weaver, Nephila pilipes is one of the largest orb weaving spiders species in the world. In terms of body size, it it second to the recently discovered N. komaci

Sexual dimorphism is very evident in spiders, particularly with this species. Female N. pilipes are much larger reaching a body size of 30-50mm (gigantism) while the males are very small with a body length of 5-6mm (dwarfism). Females are mostly black, yellow-brown with golden stripes. The back (tergum) is dark brown covered with dense hairs. Eyes appear in rows which bulge towards its rear. The bottom size of its abdomen (plastron) is mostly black and brown. Legs are very long with, black with yellow. There are no hairs found on the female spiders legs.  Male N. pilipes are 4-10 times smaller than the females. These are mainly brown to reddish brown in color. Their front eyes are larger than their rear eyes. The light brown legs possess hairs. 

DISTRIBUTION of GIANT GOLDEN ORB WEAVER SPIDER 

These giant spiders are found in tropical forest habitats of South Asia (Sri Lanka, Nepal, India), Southeast Asia (Cambodia, Indonesia, Laos, Malaysia, Singapore, Vietnam and the Philippines). They are also reported in China, Japan, Papua New Guinea and Australia. 

BIODYNAMICS NOTES

They produced large, orb like structures, composed of elastic, golden silk reaching 0.5-1.0 meter in diameter. The spider web strands are reported to be as strong and durable as kevlar! 

The hub of the spider is usually on the top of the web while it does most of its capturing of prey on the lower parts. As a predator, it employs an adaptive strategy it capturing its prey. Small captures are caught directly, removed from the web and consumed. For larger prey, venom is injected and the spider awaits for the victim to die (truly ferocious!)

N. pilipes are selective in the type of insects that they consumed. They feed mainly on flies, beetles, locust, moths and cicadas.  When other non preferred insects are captured in their web, they remove specific insects that secrete unpalatable compounds like vespid wasps and the alates (reproductives) of ants. Reports have also been made that these giant spiders can feed upon birds and bats captured on their strong web!

These spiders are observed to make food reserve caches during time of plentiful prey to enable them to deal with food shortages. When lots of prey is available, they wrap these surplus food in silk and store these in the hub section of their web. Ready made insect take out food!  

For protection against predation from birds, the spiders stays mainly on their web day and night and build a "barrier network of durable threads" on one or both sides of the web. They also vigorously shake their web to distract and also allow them to move away. 

It is important to note that these giant golden orb weaver spiders are NON AGGRESSIVE and they will not usually bite humans. In cases that you encounter their bite, this can cause muscle pain and tightness. 

A simple request, if you see a spider on its natural habitat, please don't kill it. Let is stay on its golden web. It means you no harm! It is there mainly as GENERALIST insect predator, doing its part in the natural balance of life!

It was truly an awesome encounter with this giant lady spider in the hiking trails of Mt Makiling!  

Awesome Creatures! Awesome CREATOR!

Thanks for your support and careful attention. 
If you need Pest Management Training, Technical Field Support, On-Line and On-Site Consultancy, please feel free to send me an email: odelon.reyes@gmail.com   

Thursday, August 11, 2022

An Awesome Encounter with the Eagles of the Philippine Eagle Center in Davao City

A truly awesome bird - the Philippine Eagle

The Philippine Eagle is considered the largest of the extant eagles in the world

They are also called the Monkey-eating Eagle and the Great Philippine Eagle

These raptors are the apex predators of the forest

The Philippine Eagle Center in Davao is home to these captive birds

"Mindanao" is going to be 21 years old soon

"Sinag" (ray of light) a captive-bred eagle is going to turn 7

"Marikit" (Pretty or Lovely) is a lady eagle that truly lives up to her name

My three lovely ("Marikit") ladies gazing at Marikit the Eagle 

Can you spot "Kaibigan" (Friend) in this enclosure?

Kaibigan - a 23 year old female on her make shift nest 

Showing off its top form - truly awesome!

Contemplating about the future - hopefully it will be bright for these Eagles

Awesome work and effort, Philippine Eagle Center, Davao City!

It was during my recent holiday, that our family journeyed south to explore and enjoy the beauty and wonders of Davao City, Mindanao, Philippines. As a naturalist-explorer-adventurer, one of the highlights of trip was our visit to the Philippine Eagle Center. This place is truly awesome, it simulates a rainforest environment, complete with lush greenery, tall trees and streams. There are also lots of butterflies, dragonflies and other bugs that also caught my fancy. This conservation-education-breeding center is home to 36 eagles and other raptor birds, mammals and even 2 large estuarine crocodiles! Truly an awesome place to explore and observed these awesome birds up close!  

The Philippine Eagle, Pithecophaga jeffreyi (AVES: ACCIPITRIDAE)
The Philippine Eagle bears a nape that is adorned with long, brown feathers, that exhibits a shaggy, mane-like crest. It has a dark face, creamy-brown nape and crown. Its back is wholly dark brown while the underside and underwings are white. It possessed yellow-colored heavy legs, equipped with large, powerful and dark claws and the distinguished large, high-arched and deep bluish gray beak. The piercing eyes of these apex predators are blue-gray. Adult Philippine Eagles measure 2.82 to 3.35 feet (86 to 102cm) long with a weight of 8.9 to 17.6 lbs (4.04 to 8kg). Average length was reported to be 3ft 1in (95cm) for males and 3ft5in (105cm) for females.  

The Philippine Eagle is considered as the largest of the extant eagles in the world, in terms of length and wing surface area. Wingspan is measured at 6ft to 7ft3in (184 to 220cm) and the wing chord length at 22.6-24.2 in (57.4-61.4cm). Only the Stellar Sea Eagle and Harpy Eagle are larger in terms of weight and bulk. 

Distribution of the Philippine Eagle
The Philippine Eagle is endemic to the forests of the Philippines and found mainly in the major islands of eastern Luzon, Samar, Leyte and Mindanao.  

Biodynamics Notes
A complete breeding cycle of the Philippine Eagle last for up to two years. A female becomes sexually mature at 5 years while the male takes 7 years. Similar to most eagle species, the Philippine Eagle is monogamous. Once the birds paired, the couple will stay together for the rest of their lives (now that's what you call bird commitment).
The average life span of the Philippine Eagle in the wild is 30 to 60 years. A captive bird at the Philippine Eagle Center in Davao City was reported to live up to 46 years.    
The Philippine Eagle is the most dominant predator in its Philippine forest habitat. Recent studies conducted in Davao City revealed the nearest distance between mating pairs can cover 13km (8.1mi). That is still considerable forest size, which makes these huge birds extremely vulnerable to deforestation. As apex predator of the forests, listed among its prey are the fruit bats, rats, tree squirrels, flying lemurs, flying foxes, the giant cloud rats, large snakes and lizards, large birds like owls and hornbills and also monkeys, 
I remember a story my youngest Brother, John Louie, shared with me regarding their encounter with these raptors up on the high slopes of Mt. Banahaw in Luzon. He told me that when they had a sighting of an eagle, they hurried to hide in their tents to avoid being spotted and for these young mountaineers to be mis-identified as monkeys moving across the mountain foliage. Well I don't blame them for hiding in fear, this eagle was not formerly called the Monkey-eating Eagle for nothing! 

The Philippine Eagle Center in Davao City is doing such a noble and excellent work in education, research, breeding and conservation of these majestic birds. I truly had an awesome time during our visit.

The Philippine Eagle is truly an awesome bird of prey! May it continually soar in the sky above the forests of the Philippines.  Lets protect it and conserve its natural forest habitats.           

Awesome creatures. AWESOME CREATOR!

Thanks for your support and careful attention. 
If you need Pest Management Training, Technical Field Support, On-Line and On-Site Consultancy, please feel free to send me an email: odelon.reyes@gmail.com