28-29 March: Ospreys are monogamous.... but...

An unringed female stopped for a couple of days during her migration northwards and paid a brief visit to the nest of 03(97). There she was given a warm welcome - that's 03(97) above and the female with a very heavily marked breast below. Field Offficer, John Wright was able to see that she was unringed and, comparing her head patterns with sketches made last year, John was certain that she was a different female from those we saw for brief periods last summer.

Compare the size of the nest now with what it was like just a week before. 03 had certainly been busy!

 

1 April: return of the breeding female

05(00), the established mate of 03(97), returned to the nest site, arriving a full fortnight earlier than in 2003 and 2004.

Field officer, Tim Mackrill, had seen from a distance the male 03(97) displaying with a fish and calling. He drove quickly to the nest site and was amazed to see the male giving a fish to a familiar looking female Osprey . Very soon he could read the ring number: 05 on a green ring on the right leg.

Fortunately the unringed female, pictured above, had moved on, so there was no need for 05(00) to fight to re-establish her rightful place at the nest where she has mothered 5 chicks.

2 -19 April: the settling down period

On 2 April, the female 05(00) was hardly at her nest site at all, instead going to Manton Bay where she was wooed by 08(97). She sat on his newly re-furbished artificial nest but wasn't having any truck with his advances. 03(97) wasn't too disturbed by her defection and just kept on with the DIY at his nest.

Later the female was also seen visiting the new nest platform that had been firmly adopted by 09(98).

However, on 3 April 05(00) returned home and spent much of the day begging to be fed by her mate 03(97). He wasn't much impressed by her behaviour and we didn't see him provide the fish she craved.

But by 6 April the pair had settled and spent much of the time building up their nest and with the male doing most of the fishing.

Incubation

With the breeding pair together again, they were monitored closely by the large team of staff and volunteers.

Eventually, egg-laying was observed and by the end of April incubation was well underway.

The weather during May was very poor, with violent storms and persistent cold winds from north but the male kept on fishing and the female (mostly) kept on sitting. The monitors had very little action to record but fish supplies (times and species), weather conditions, avian intruders, and incubation duties were all noted and analysed.

Another incubation picture 16 May
- the female sitting on the eggs and the male above with the wind behind him

  29 May: hatching

On the 38th day of incubation, at 6am we were able to confirm that one at least of the eggs had hatched when the female 05(00), while sitting fairly high in the nest, was seen to tear a piece of fish and offer it down to something beside her.

The pair's behaviour had been changing in the few days previously, with the adults standing on the nest and cocking heads to one side in a listening posture. Then on the previous morning the male did what volunteers Ray and Maureen Broad described as a "victory roll".

Overnight the female was very restless and at first light she was seen to be feeding herself in the nest, but when we saw her offer a fish fragment downwards we were sure that there was new life down there in the nest. The male celebrated by bringing three fish to the nest during the day and doing some very obvious feeding of his young during the morning.

Fortunately the weather and the forecast for the next few days were good. It will be a couple of weeks before we are able to count heads and know how many chicks have been produced this year.

Early June: how many chicks?

Without the benefit of a camera looking down into the nest, we were unable to answer the question. Instead staff and volunteers monitoring the nest engaged in the usual guessing game along the lines of:

"I'm sure she's presenting fish fragments in different positions. There must be 2 (or 3, or...!) "

12 June: it's three!

Opinion was hardening that there were only two chicks. Then, volunteer Chris Nelson, doiing the early morning shift, was convinced that she could see the tops of three tiny heads showing above the rim of the nest.

Within a few days the three young had grown, so that all three could be seen clearly for much of the time - except when rain brought the adult female to spread herself over them, protecting them from the worst ravages of the weather.

As the chicks grow, their food consumption increases and 03(97) is now bringing in at least 4 fish per day. The female generally does the feeding, tearing and distributing small pieces of flesh to the three chicks in turn.

The male, in front, offering fish to the newly hatched young, hidden deep in the nest

18 June: Three weeks old and growing fast

The development of the chicks at this age is dramatic: every day they seem visibly bigger and more active. They clearly take their cue from mother at this point - how else could you explain the sight of them moving tiny twigs around the nest?

With the first hot, bright sunshine of the summer, we have seen 05(00) sitting with her wings spread out in order to provide shade for the still-fragile chicks. She has also been bringing in extra nest lining material to make the nest less deep and the sides more accessible for the chicks.

7 July:  Ringing

Today, the three chicks had yellow plastic rings, numbered 30, 31 and 32 fitted to their right legs and a standard metal BTO ring on their left leg. All three were in excellent condition. Within an hour the three were back on the nest and mother was back with them, almost as soon as the ringing team disappeared.

Our visit to the nest tree provided two surprises:

• signs of intense fox activity at the base of the tree - no doubt taking advantage of the dropped pieces of fish.
• pieces of corn on the cob (maize) decorating the inside of the nest - presumably used as part of the nest lining.

18 July: First flight in a squall

On 18 July the weather changed. After nearly a week of hot, windless, sultry weather, a cooler wind arrrived from the north-west bringing sudden heavy thundery showers. This change was just what was needed to provoke one of the chicks at the breeding nest to launch itself into the air for the first time.

For days they had been thinking about it, with hops across the nest, multiple wingflaps and lifting up a few feet. The adults had been recorded flying low and slow past the nest, calling to the young. The monitors had been on the edge of their seats and confidently predicting that it would come at any time.

Then when it was least expected, with humans racing for cover from the rain, one chick suddenly took off. Up and up she circled (we think it was one of the two females) with the adults flying nearby and calling. Four full minutes the flight lasted before the juvenile landed back, with some precision, on the nest.

A very exciting experience for volunteers John and Sheila Davies, who were the lucky ones to witness it all. Very soon the phone lines were buzzing with the brilliant news and expectations that the next few days would be very exciting ones with more early flights being seen.

One of the female chicks returns to the nest after one of her many short flights on 21 July.

22 July: More flights - eventually!

Well, we were wrong. For the next few days no further flights by the chicks were seen at all. It could be that the first flight during the rain squall was in fact an involuntary one. It was not until the morning of 21 July that we saw regular short flights by both the female chicks, with ring numbers 30 and 31.

 

 

 

 

 

 

27 July: Juveniles out of sight

All three juveniles are now flying and spending time away from the nest. However, they keep returning to the nest where the fish keep being delivered by the parents.

The volunteers monitoring the nest throughout the day are recording short absences by the youngsters as they fly off to sit on other nearby perches. It will probably be some time before they are seen at the reservoir.  

31 July: Juvenile "playing with gulls"

The first confirmed sighting of one of the female juveniles this morning. John Wright saw her flying around the shoreline of the north arm of the reservoir. She was chasing and being chased by a group of gulls.

13 August: the whole family still here

All three young and both parents are still using the nest, although they spend longer and longer away from it.

Unlike last year, when there was lots of disturbance from other non-breeding adults, the nest area has been relatively intruder-free.

22 August: has mother gone?

It could be that 05(00), the adult female. has finally left Rutland. She was seen briefly after 2 days' absence on Saturday 20 August by volunteer Martin Blee.

Since then she has not been recorded, though the three juveniles and their father 03(97) are still returning regularly the nest. In 2004 she was last seen on 30 August.

26 August: a final sighting

Although not recorded again at the breeding nest site, 05(00) was seen by Tim Mackrill at one of the artificail nests today. It was the last time she ws recorded this year.

One of the juveniles looking in fine fettle and ready to migrate

 31 August: but Dad keps up the food supply

Volunteers and staff are maintaining daily visits to the nest site to record which of the family are still present.

03(97) the adult male is still frequently present as are various of the three juveniles, females 30 and 31, and male 32. Recenty one the the three juveniles was recorded sitting at the edge of the reservoir beside the adult non-breeding male, 09(98).

3 September: the family go

Yesterday the last juvenile was recorded at the nest and today.

POSTCRIPT: 2007

Two of the youngsters, 30(05) and 32(05) returned to Rutland in 2007 - for details please click here.